Beam Failure Recovery Request Procedure

ABSTRACT

A wireless device initiates a beam failure recovery procedure in response to detecting a number of beam failure instances based on a first plurality of reference signals. A beam failure recovery timer is started with a timer value in response to the detecting. A physical layer of the wireless device assesses, during the beam failure recovery timer running, a first radio link quality of a second plurality of reference signals against a threshold. The beam failure recovery procedure is completed in response to the beam failure recovery timer expiring and the first radio link quality being below the threshold. Information indicating that the beam failure recovery procedure failed due to the first radio link quality being below the threshold is reported to a radio resource control layer of the wireless device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/626,328, filed Feb. 5, 2018, which are hereby incorporated byreference in its entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present disclosureare described herein with reference to the drawings.

FIG. 1 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 2A is a diagram of an example user plane protocol stack as per anaspect of an embodiment of the present disclosure.

FIG. 2B is a diagram of an example control plane protocol stack as peran aspect of an embodiment of the present disclosure.

FIG. 3 is a diagram of an example wireless device and two base stationsas per an aspect of an embodiment of the present disclosure.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals as per an aspect of an embodiment of the presentdisclosure.

FIG. 5B is a diagram of an example downlink channel mapping and exampledownlink physical signals as per an aspect of an embodiment of thepresent disclosure.

FIG. 6 is a diagram depicting an example transmission time or receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure.

FIG. 7A and FIG. 7B are diagrams depicting example sets of OFDMsubcarriers as per an aspect of an embodiment of the present disclosure.

FIG. 8 is a diagram depicting example OFDM radio resources as per anaspect of an embodiment of the present disclosure.

FIG. 9A is a diagram depicting an example CSI-RS and/or SS blocktransmission in a multi-beam system.

FIG. 9B is a diagram depicting an example downlink beam managementprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 10 is an example diagram of configured BWPs as per an aspect of anembodiment of the present disclosure.

FIG. 11A, and FIG. 11B are diagrams of an example multi connectivity asper an aspect of an embodiment of the present disclosure.

FIG. 12 is a diagram of an example random access procedure as per anaspect of an embodiment of the present disclosure.

FIG. 13 is a structure of example MAC entities as per an aspect of anembodiment of the present disclosure.

FIG. 14 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 15 is a diagram of example RRC states as per an aspect of anembodiment of the present disclosure.

FIG. 16A and FIG. 16B are examples of downlink beam failure scenario asper an aspect of an embodiment of the present disclosure.

FIG. 17 is an example of downlink beam failure recovery requestprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 18 is an example of downlink beam failure recovery procedure as peran aspect of an embodiment of the present disclosure.

FIG. 19 is an example of downlink beam failure recovery procedure as peran aspect of an embodiment of the present disclosure.

FIG. 20 is an example of a beam failure recovery as per an aspect of anembodiment of the present disclosure.

FIG. 21 is an example flow diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 22A and FIG. 22B are example flow diagrams of aspects of anembodiment of the present disclosure.

FIG. 23A and FIG. 23B are example flow diagrams of aspects of anembodiment of the present disclosure.

FIG. 24A and FIG. 24B are example flow diagrams of aspects of anembodiment of the present disclosure.

FIG. 25A and FIG. 25B are example flow diagrams of aspects of anembodiment of the present disclosure.

FIG. 26 is an example flow diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 27 is an example flow diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 28 is an example flow diagram of an aspect of an embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments of the present disclosure enable operation of beamfailure recovery request procedure. Embodiments of the technologydisclosed herein may be employed in the technical field of multicarriercommunication systems. More particularly, the embodiments of thetechnology disclosed herein may relate to beam failure recovery requestprocedure in a multicarrier communication system.

The following Acronyms are used throughout the present disclosure:

3GPP 3rd Generation Partnership Project

5GC 5G Core Network

ACK Acknowledgement

AMF Access and Mobility Management Function

ARQ Automatic Repeat Request

AS Access Stratum

ASIC Application-Specific Integrated Circuit

BA Bandwidth Adaptation

BCCH Broadcast Control Channel

BCH Broadcast Channel

BPSK Binary Phase Shift Keying

BWP Bandwidth Part

CA Carrier Aggregation

CC Component Carrier

CCCH Common Control CHannel

CDMA Code Division Multiple Access

CN Core Network

CP Cyclic Prefix

CP-OFDM Cyclic Prefix-Orthogonal Frequency Division Multiplex

C-RNTI Cell-Radio Network Temporary Identifier

CS Configured Scheduling

CSI Channel State Information

CSI-RS Channel State Information-Reference Signal

CQI Channel Quality Indicator

CSS Common Search Space

CU Central Unit

DC Dual Connectivity

DCCH Dedicated Control Channel

DCI Downlink Control Information

DL Downlink

DL-SCH Downlink Shared CHannel

DM-RS DeModulation Reference Signal

DRB Data Radio Bearer

DRX Discontinuous Reception

DTCH Dedicated Traffic Channel

DU Distributed Unit

EPC Evolved Packet Core

E-UTRA Evolved UMTS Terrestrial Radio Access

E-UTRAN Evolved-Universal Terrestrial Radio Access Network

FDD Frequency Division Duplex

FPGA Field Programmable Gate Arrays

F1-C F1-Control plane

F1-U F1-User plane

gNB next generation Node B

HARQ Hybrid Automatic Repeat reQuest

HDL Hardware Description Languages

IE Information Element

IP Internet Protocol

LCID Logical Channel Identifier

LTE Long Term Evolution

MAC Media Access Control

MCG Master Cell Group

MCS Modulation and Coding Scheme

MeNB Master evolved Node B

MIB Master Information Block

MME Mobility Management Entity

MN Master Node

NACK Negative Acknowledgement

NAS Non-Access Stratum

NG CP Next Generation Control Plane

NGC Next Generation Core

NG-C NG-Control plane

ng-eNB next generation evolved Node B

NG-U NG-User plane

NR New Radio

NR MAC New Radio MAC

NR PDCP New Radio PDCP

NR PHY New Radio PHYsical

NR RLC New Radio RLC

NR RRC New Radio RRC

NSSAI Network Slice Selection Assistance Information

O&M Operation and Maintenance

OFDM orthogonal Frequency Division Multiplexing

PBCH Physical Broadcast CHannel

PCC Primary Component Carrier

PCCH Paging Control CHannel

PCell Primary Cell

PCH Paging CHannel

PDCCH Physical Downlink Control CHannel

PDCP Packet Data Convergence Protocol

PDSCH Physical Downlink Shared CHannel

PDU Protocol Data Unit

PHICH Physical HARQ Indicator CHannel

PHY PHYsical

PLMN Public Land Mobile Network

PMI Precoding Matrix Indicator

PRACH Physical Random Access CHannel

PRB Physical Resource Block

PSCell Primary Secondary Cell

PSS Primary Synchronization Signal

pTAG primary Timing Advance Group

PT-RS Phase Tracking Reference Signal

PUCCH Physical Uplink Control CHannel

PUSCH Physical Uplink Shared CHannel

QAM Quadrature Amplitude Modulation

QFI Quality of Service Indicator

QoS Quality of Service

QPSK Quadrature Phase Shift Keying

RA Random Access

RACH Random Access CHannel

RAN Radio Access Network

RAT Radio Access Technology

RA-RNTI Random Access-Radio Network Temporary Identifier

RB Resource Blocks

RBG Resource Block Groups

RI Rank indicator

RLC Radio Link Control

RRC Radio Resource Control

RS Reference Signal

RSRP Reference Signal Received Power

SCC Secondary Component Carrier

SCell Secondary Cell

SCG Secondary Cell Group

SC-FDMA Single Carrier-Frequency Division Multiple Access

SDAP Service Data Adaptation Protocol

SDU Service Data Unit

SeNB Secondary evolved Node B

SFN System Frame Number

S-GW Serving GateWay

SI System Information

SIB System Information Block

SMF Session Management Function

SN Secondary Node

SpCell Special Cell

SRB Signaling Radio Bearer

SRS Sounding Reference Signal

SS Synchronization Signal

SSS Secondary Synchronization Signal

sTAG secondary Timing Advance Group

TA Timing Advance

TAG Timing Advance Group

TAI Tracking Area Identifier

TAT Time Alignment Timer

TB Transport Block

TC-RNTI Temporary Cell-Radio Network Temporary Identifier

TDD Time Division Duplex

TDMA Time Division Multiple Access

TTI Transmission Time Interval

UCI Uplink Control Information

UE User Equipment

UL Uplink

UL-SCH Uplink Shared CHannel

UPF User Plane Function

UPGW User Plane Gateway

VHDL VHSIC Hardware Description Language

Xn-C Xn-Control plane

Xn-U Xn-User plane

Example embodiments of the disclosure may be implemented using variousphysical layer modulation and transmission mechanisms. Exampletransmission mechanisms may include, but are not limited to: CodeDivision Multiple Access (CDMA), Orthogonal Frequency Division MultipleAccess (OFDMA), Time Division Multiple Access (TDMA), Wavelettechnologies, and/or the like. Hybrid transmission mechanisms such asTDMA/CDMA, and OFDM/CDMA may also be employed. Various modulationschemes may be applied for signal transmission in the physical layer.Examples of modulation schemes include, but are not limited to: phase,amplitude, code, a combination of these, and/or the like. An exampleradio transmission method may implement Quadrature Amplitude Modulation(QAM) using Binary Phase Shift Keying (BPSK), Quadrature Phase ShiftKeying (QPSK), 16-QAM, 64-QAM, 256-QAM, and/or the like. Physical radiotransmission may be enhanced by dynamically or semi-dynamically changingthe modulation and coding scheme depending on transmission requirementsand radio conditions.

FIG. 1 is an example Radio Access Network (RAN) architecture as per anaspect of an embodiment of the present disclosure. As illustrated inthis example, a RAN node may be a next generation Node B (gNB) (e.g.120A, 120B) providing New Radio (NR) user plane and control planeprotocol terminations towards a first wireless device (e.g. 110A). In anexample, a RAN node may be a next generation evolved Node B (ng-eNB)(e.g. 120C, 120D), providing Evolved UMTS Terrestrial Radio Access(E-UTRA) user plane and control plane protocol terminations towards asecond wireless device (e.g. 110B). The first wireless device maycommunicate with a gNB over a Uu interface. The second wireless devicemay communicate with a ng-eNB over a Uu interface.

A gNB or an ng-eNB may host functions such as radio resource managementand scheduling, IP header compression, encryption and integrityprotection of data, selection of Access and Mobility Management Function(AMF) at User Equipment (UE) attachment, routing of user plane andcontrol plane data, connection setup and release, scheduling andtransmission of paging messages (originated from the AMF), schedulingand transmission of system broadcast information (originated from theAMF or Operation and Maintenance (O&M)), measurement and measurementreporting configuration, transport level packet marking in the uplink,session management, support of network slicing, Quality of Service (QoS)flow management and mapping to data radio bearers, support of UEs inRRC_INACTIVE state, distribution function for Non-Access Stratum (NAS)messages, RAN sharing, dual connectivity or tight interworking betweenNR and E-UTRA.

In an example, one or more gNBs and/or one or more ng-eNBs may beinterconnected with each other by means of Xn interface. A gNB or anng-eNB may be connected by means of NG interfaces to 5G Core Network(5GC). In an example, 5GC may comprise one or more AMF/User PlanFunction (UPF) functions (e.g. 130A or 130B). A gNB or an ng-eNB may beconnected to a UPF by means of an NG-User plane (NG-U) interface. TheNG-U interface may provide delivery (e.g. non-guaranteed delivery) ofuser plane Protocol Data Units (PDUs) between a RAN node and the UPF. AgNB or an ng-eNB may be connected to an AMF by means of an NG-Controlplane (NG-C) interface. The NG-C interface may provide functions such asNG interface management, UE context management, UE mobility management,transport of NAS messages, paging, PDU session management, configurationtransfer or warning message transmission.

In an example, a UPF may host functions such as anchor point forintra-/inter-Radio Access Technology (RAT) mobility (when applicable),external PDU session point of interconnect to data network, packetrouting and forwarding, packet inspection and user plane part of policyrule enforcement, traffic usage reporting, uplink classifier to supportrouting traffic flows to a data network, branching point to supportmulti-homed PDU session, QoS handling for user plane, e.g. packetfiltering, gating, Uplink (UL)/Downlink (DL) rate enforcement, uplinktraffic verification (e.g. Service Data Flow (SDF) to QoS flow mapping),downlink packet buffering and/or downlink data notification triggering.

In an example, an AMF may host functions such as NAS signalingtermination, NAS signaling security, Access Stratum (AS) securitycontrol, inter Core Network (CN) node signaling for mobility between3^(rd) Generation Partnership Project (3GPP) access networks, idle modeUE reachability (e.g., control and execution of paging retransmission),registration area management, support of intra-system and inter-systemmobility, access authentication, access authorization including check ofroaming rights, mobility management control (subscription and policies),support of network slicing and/or Session Management Function (SMF)selection.

FIG. 2A is an example user plane protocol stack, where Service DataAdaptation Protocol (SDAP) (e.g. 211 and 221), Packet Data ConvergenceProtocol (PDCP) (e.g. 212 and 222), Radio Link Control (RLC) (e.g. 213and 223) and Media Access Control (MAC) (e.g. 214 and 224) sublayers andPhysical (PHY) (e.g. 215 and 225) layer may be terminated in wirelessdevice (e.g. 110) and gNB (e.g. 120) on the network side. In an example,a PHY layer provides transport services to higher layers (e.g. MAC, RRC,etc.). In an example, services and functions of a MAC sublayer maycomprise mapping between logical channels and transport channels,multiplexing/demultiplexing of MAC Service Data Units (SDUs) belongingto one or different logical channels into/from Transport Blocks (TBs)delivered to/from the PHY layer, scheduling information reporting, errorcorrection through Hybrid Automatic Repeat request (HARQ) (e.g. one HARQentity per carrier in case of Carrier Aggregation (CA)), priorityhandling between UEs by means of dynamic scheduling, priority handlingbetween logical channels of one UE by means of logical channelprioritization, and/or padding. A MAC entity may support one or multiplenumerologies and/or transmission timings. In an example, mappingrestrictions in a logical channel prioritization may control whichnumerology and/or transmission timing a logical channel may use. In anexample, an RLC sublayer may supports transparent mode (TM),unacknowledged mode (UM) and acknowledged mode (AM) transmission modes.The RLC configuration may be per logical channel with no dependency onnumerologies and/or Transmission Time Interval (TTI) durations. In anexample, Automatic Repeat Request (ARQ) may operate on any of thenumerologies and/or TTI durations the logical channel is configuredwith. In an example, services and functions of the PDCP layer for theuser plane may comprise sequence numbering, header compression anddecompression, transfer of user data, reordering and duplicatedetection, PDCP PDU routing (e.g. in case of split bearers),retransmission of PDCP SDUs, ciphering, deciphering and integrityprotection, PDCP SDU discard, PDCP re-establishment and data recoveryfor RLC AM, and/or duplication of PDCP PDUs. In an example, services andfunctions of SDAP may comprise mapping between a QoS flow and a dataradio bearer. In an example, services and functions of SDAP may comprisemapping Quality of Service Indicator (QFI) in DL and UL packets. In anexample, a protocol entity of SDAP may be configured for an individualPDU session.

FIG. 2B is an example control plane protocol stack where PDCP (e.g. 233and 242), RLC (e.g. 234 and 243) and MAC (e.g. 235 and 244) sublayersand PHY (e.g. 236 and 245) layer may be terminated in wireless device(e.g. 110) and gNB (e.g. 120) on a network side and perform service andfunctions described above. In an example, RRC (e.g. 232 and 241) may beterminated in a wireless device and a gNB on a network side. In anexample, services and functions of RRC may comprise broadcast of systeminformation related to AS and NAS, paging initiated by 5GC or RAN,establishment, maintenance and release of an RRC connection between theUE and RAN, security functions including key management, establishment,configuration, maintenance and release of Signaling Radio Bearers (SRBs)and Data Radio Bearers (DRBs), mobility functions, QoS managementfunctions, UE measurement reporting and control of the reporting,detection of and recovery from radio link failure, and/or NAS messagetransfer to/from NAS from/to a UE. In an example, NAS control protocol(e.g. 231 and 251) may be terminated in the wireless device and AMF(e.g. 130) on a network side and may perform functions such asauthentication, mobility management between a UE and a AMF for 3GPPaccess and non-3GPP access, and session management between a UE and aSMF for 3GPP access and non-3GPP access.

In an example, a base station may configure a plurality of logicalchannels for a wireless device. A logical channel in the plurality oflogical channels may correspond to a radio bearer and the radio bearermay be associated with a QoS requirement. In an example, a base stationmay configure a logical channel to be mapped to one or moreTTIs/numerologies in a plurality of TTIs/numerologies. The wirelessdevice may receive a Downlink Control Information (DCI) via PhysicalDownlink Control CHannel (PDCCH) indicating an uplink grant. In anexample, the uplink grant may be for a first TTI/numerology and mayindicate uplink resources for transmission of a transport block. Thebase station may configure each logical channel in the plurality oflogical channels with one or more parameters to be used by a logicalchannel prioritization procedure at the MAC layer of the wirelessdevice. The one or more parameters may comprise priority, prioritizedbit rate, etc. A logical channel in the plurality of logical channelsmay correspond to one or more buffers comprising data associated withthe logical channel. The logical channel prioritization procedure mayallocate the uplink resources to one or more first logical channels inthe plurality of logical channels and/or one or more MAC ControlElements (CEs). The one or more first logical channels may be mapped tothe first TTI/numerology. The MAC layer at the wireless device maymultiplex one or more MAC CEs and/or one or more MAC SDUs (e.g., logicalchannel) in a MAC PDU (e.g., transport block). In an example, the MACPDU may comprise a MAC header comprising a plurality of MAC sub-headers.A MAC sub-header in the plurality of MAC sub-headers may correspond to aMAC CE or a MAC SUD (logical channel) in the one or more MAC CEs and/orone or more MAC SDUs. In an example, a MAC CE or a logical channel maybe configured with a Logical Channel IDentifier (LCID). In an example,LCID for a logical channel or a MAC CE may be fixed/pre-configured. Inan example, LCID for a logical channel or MAC CE may be configured forthe wireless device by the base station. The MAC sub-headercorresponding to a MAC CE or a MAC SDU may comprise LCID associated withthe MAC CE or the MAC SDU.

In an example, a base station may activate and/or deactivate and/orimpact one or more processes (e.g., set values of one or more parametersof the one or more processes or start and/or stop one or more timers ofthe one or more processes) at the wireless device by employing one ormore MAC commands. The one or more MAC commands may comprise one or moreMAC control elements. In an example, the one or more processes maycomprise activation and/or deactivation of PDCP packet duplication forone or more radio bearers. The base station may transmit a MAC CEcomprising one or more fields, the values of the fields indicatingactivation and/or deactivation of PDCP duplication for the one or moreradio bearers. In an example, the one or more processes may compriseChannel State Information (CSI) transmission of on one or more cells.The base station may transmit one or more MAC CEs indicating activationand/or deactivation of the CSI transmission on the one or more cells. Inan example, the one or more processes may comprise activation ordeactivation of one or more secondary cells. In an example, the basestation may transmit a MA CE indicating activation or deactivation ofone or more secondary cells. In an example, the base station maytransmit one or more MAC CEs indicating starting and/or stopping one ormore Discontinuous Reception (DRX) timers at the wireless device. In anexample, the base station may transmit one or more MAC CEs indicatingone or more timing advance values for one or more Timing Advance Groups(TAGs).

FIG. 3 is a block diagram of base stations (base station 1, 120A, andbase station 2, 120B) and a wireless device 110. A wireless device maybe called an UE. A base station may be called a NB, eNB, gNB, and/orng-eNB. In an example, a wireless device and/or a base station may actas a relay node. The base station 1, 120A, may comprise at least onecommunication interface 320A (e.g. a wireless modem, an antenna, a wiredmodem, and/or the like), at least one processor 321A, and at least oneset of program code instructions 323A stored in non-transitory memory322A and executable by the at least one processor 321A. The base station2, 120B, may comprise at least one communication interface 320B, atleast one processor 321B, and at least one set of program codeinstructions 323B stored in non-transitory memory 322B and executable bythe at least one processor 321B.

A base station may comprise many sectors for example: 1, 2, 3, 4, or 6sectors. A base station may comprise many cells, for example, rangingfrom 1 to 50 cells or more. A cell may be categorized, for example, as aprimary cell or secondary cell. At Radio Resource Control (RRC)connection establishment/re-establishment/handover, one serving cell mayprovide the NAS (non-access stratum) mobility information (e.g. TrackingArea Identifier (TAI)). At RRC connection re-establishment/handover, oneserving cell may provide the security input. This cell may be referredto as the Primary Cell (PCell). In the downlink, a carrier correspondingto the PCell may be a DL Primary Component Carrier (PCC), while in theuplink, a carrier may be an UL PCC. Depending on wireless devicecapabilities, Secondary Cells (SCells) may be configured to formtogether with a PCell a set of serving cells. In a downlink, a carriercorresponding to an SCell may be a downlink secondary component carrier(DL SCC), while in an uplink, a carrier may be an uplink secondarycomponent carrier (UL SCC). An SCell may or may not have an uplinkcarrier.

A cell, comprising a downlink carrier and optionally an uplink carrier,may be assigned a physical cell ID and a cell index. A carrier (downlinkor uplink) may belong to one cell. The cell ID or cell index may alsoidentify the downlink carrier or uplink carrier of the cell (dependingon the context it is used). In the disclosure, a cell ID may be equallyreferred to a carrier ID, and a cell index may be referred to a carrierindex. In an implementation, a physical cell ID or a cell index may beassigned to a cell. A cell ID may be determined using a synchronizationsignal transmitted on a downlink carrier. A cell index may be determinedusing RRC messages. For example, when the disclosure refers to a firstphysical cell ID for a first downlink carrier, the disclosure may meanthe first physical cell ID is for a cell comprising the first downlinkcarrier. The same concept may apply to, for example, carrier activation.When the disclosure indicates that a first carrier is activated, thespecification may equally mean that a cell comprising the first carrieris activated.

A base station may transmit to a wireless device one or more messages(e.g. RRC messages) comprising a plurality of configuration parametersfor one or more cells. One or more cells may comprise at least oneprimary cell and at least one secondary cell. In an example, an RRCmessage may be broadcasted or unicasted to the wireless device. In anexample, configuration parameters may comprise common parameters anddedicated parameters.

Services and/or functions of an RRC sublayer may comprise at least oneof: broadcast of system information related to AS and NAS; paginginitiated by 5GC and/or NG-RAN; establishment, maintenance, and/orrelease of an RRC connection between a wireless device and NG-RAN, whichmay comprise at least one of addition, modification and release ofcarrier aggregation; or addition, modification, and/or release of dualconnectivity in NR or between E-UTRA and NR. Services and/or functionsof an RRC sublayer may further comprise at least one of securityfunctions comprising key management; establishment, configuration,maintenance, and/or release of Signaling Radio Bearers (SRBs) and/orData Radio Bearers (DRBs); mobility functions which may comprise atleast one of a handover (e.g. intra NR mobility or inter-RAT mobility)and a context transfer; or a wireless device cell selection andreselection and control of cell selection and reselection. Servicesand/or functions of an RRC sublayer may further comprise at least one ofQoS management functions; a wireless device measurementconfiguration/reporting; detection of and/or recovery from radio linkfailure; or NAS message transfer to/from a core network entity (e.g.AMF, Mobility Management Entity (MME)) from/to the wireless device.

An RRC sublayer may support an RRC_Idle state, an RRC_Inactive stateand/or an RRC_Connected state for a wireless device. In an RRC_Idlestate, a wireless device may perform at least one of: Public Land MobileNetwork (PLMN) selection; receiving broadcasted system information; cellselection/re-selection; monitoring/receiving a paging for mobileterminated data initiated by 5GC; paging for mobile terminated data areamanaged by 5GC; or DRX for CN paging configured via NAS. In anRRC_Inactive state, a wireless device may perform at least one of:receiving broadcasted system information; cell selection/re-selection;monitoring/receiving a RAN/CN paging initiated by NG-RAN/5GC; RAN-basednotification area (RNA) managed by NG-RAN; or DRX for RAN/CN pagingconfigured by NG-RAN/NAS. In an RRC_Idle state of a wireless device, abase station (e.g. NG-RAN) may keep a 5GC-NG-RAN connection (bothC/U-planes) for the wireless device; and/or store a UE AS context forthe wireless device. In an RRC_Connected state of a wireless device, abase station (e.g. NG-RAN) may perform at least one of: establishment of5GC-NG-RAN connection (both C/U-planes) for the wireless device; storinga UE AS context for the wireless device; transmit/receive of unicastdata to/from the wireless device; or network-controlled mobility basedon measurement results received from the wireless device. In anRRC_Connected state of a wireless device, an NG-RAN may know a cell thatthe wireless device belongs to.

System information (SI) may be divided into minimum SI and other SI. Theminimum SI may be periodically broadcast. The minimum SI may comprisebasic information required for initial access and information foracquiring any other SI broadcast periodically or provisioned on-demand,i.e. scheduling information. The other SI may either be broadcast, or beprovisioned in a dedicated manner, either triggered by a network or uponrequest from a wireless device. A minimum SI may be transmitted via twodifferent downlink channels using different messages (e.g.MasterInformationBlock and SystemInformationBlockType1). Another SI maybe transmitted via SystemInformationBlockType2. For a wireless device inan RRC_Connected state, dedicated RRC signaling may be employed for therequest and delivery of the other SI. For the wireless device in theRRC_Idle state and/or the RRC_Inactive state, the request may trigger arandom-access procedure.

A wireless device may report its radio access capability informationwhich may be static. A base station may request what capabilities for awireless device to report based on band information. When allowed by anetwork, a temporary capability restriction request may be sent by thewireless device to signal the limited availability of some capabilities(e.g. due to hardware sharing, interference or overheating) to the basestation. The base station may confirm or reject the request. Thetemporary capability restriction may be transparent to 5GC (e.g., staticcapabilities may be stored in 5GC).

When CA is configured, a wireless device may have an RRC connection witha network. At RRC connection establishment/re-establishment/handoverprocedure, one serving cell may provide NAS mobility information, and atRRC connection re-establishment/handover, one serving cell may provide asecurity input. This cell may be referred to as the PCell. Depending onthe capabilities of the wireless device, SCells may be configured toform together with the PCell a set of serving cells. The configured setof serving cells for the wireless device may comprise one PCell and oneor more SCells.

The reconfiguration, addition and removal of SCells may be performed byRRC. At intra-NR handover, RRC may also add, remove, or reconfigureSCells for usage with the target PCell. When adding a new SCell,dedicated RRC signaling may be employed to send all required systeminformation of the SCell i.e. while in connected mode, wireless devicesmay not need to acquire broadcasted system information directly from theSCells.

The purpose of an RRC connection reconfiguration procedure may be tomodify an RRC connection, (e.g. to establish, modify and/or release RBs,to perform handover, to setup, modify, and/or release measurements, toadd, modify, and/or release SCells and cell groups). As part of the RRCconnection reconfiguration procedure, NAS dedicated information may betransferred from the network to the wireless device. TheRRCConnectionReconfiguration message may be a command to modify an RRCconnection. It may convey information for measurement configuration,mobility control, radio resource configuration (e.g. RBs, MAC mainconfiguration and physical channel configuration) comprising anyassociated dedicated NAS information and security configuration. If thereceived RRC Connection Reconfiguration message includes thesCellToReleaseList, the wireless device may perform an SCell release. Ifthe received RRC Connection Reconfiguration message includes thesCellToAddModList, the wireless device may perform SCell additions ormodification.

An RRC connection establishment (or reestablishment, resume) proceduremay be to establish (or reestablish, resume) an RRC connection. an RRCconnection establishment procedure may comprise SRB1 establishment. TheRRC connection establishment procedure may be used to transfer theinitial NAS dedicated information/message from a wireless device toE-UTRAN. The RRCConnectionReestablishment message may be used tore-establish SRB 1.

A measurement report procedure may be to transfer measurement resultsfrom a wireless device to NG-RAN. The wireless device may initiate ameasurement report procedure after successful security activation. Ameasurement report message may be employed to transmit measurementresults.

The wireless device 110 may comprise at least one communicationinterface 310 (e.g. a wireless modem, an antenna, and/or the like), atleast one processor 314, and at least one set of program codeinstructions 316 stored in non-transitory memory 315 and executable bythe at least one processor 314. The wireless device 110 may furthercomprise at least one of at least one speaker/microphone 311, at leastone keypad 312, at least one display/touchpad 313, at least one powersource 317, at least one global positioning system (GPS) chipset 318,and other peripherals 319.

The processor 314 of the wireless device 110, the processor 321A of thebase station 1 120A, and/or the processor 321B of the base station 2120B may comprise at least one of a general-purpose processor, a digitalsignal processor (DSP), a controller, a microcontroller, an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) and/or other programmable logic device, discrete gate and/ortransistor logic, discrete hardware components, and the like. Theprocessor 314 of the wireless device 110, the processor 321A in basestation 1 120A, and/or the processor 321B in base station 2 120B mayperform at least one of signal coding/processing, data processing, powercontrol, input/output processing, and/or any other functionality thatmay enable the wireless device 110, the base station 1 120A and/or thebase station 2 120B to operate in a wireless environment.

The processor 314 of the wireless device 110 may be connected to thespeaker/microphone 311, the keypad 312, and/or the display/touchpad 313.The processor 314 may receive user input data from and/or provide useroutput data to the speaker/microphone 311, the keypad 312, and/or thedisplay/touchpad 313. The processor 314 in the wireless device 110 mayreceive power from the power source 317 and/or may be configured todistribute the power to the other components in the wireless device 110.The power source 317 may comprise at least one of one or more dry cellbatteries, solar cells, fuel cells, and the like. The processor 314 maybe connected to the GPS chipset 318. The GPS chipset 318 may beconfigured to provide geographic location information of the wirelessdevice 110.

The processor 314 of the wireless device 110 may further be connected toother peripherals 319, which may comprise one or more software and/orhardware modules that provide additional features and/orfunctionalities. For example, the peripherals 319 may comprise at leastone of an accelerometer, a satellite transceiver, a digital camera, auniversal serial bus (USB) port, a hands-free headset, a frequencymodulated (FM) radio unit, a media player, an Internet browser, and thelike.

The communication interface 320A of the base station 1, 120A, and/or thecommunication interface 320B of the base station 2, 120B, may beconfigured to communicate with the communication interface 310 of thewireless device 110 via a wireless link 330A and/or a wireless link 330Brespectively. In an example, the communication interface 320A of thebase station 1, 120A, may communicate with the communication interface320B of the base station 2 and other RAN and core network nodes.

The wireless link 330A and/or the wireless link 330B may comprise atleast one of a bi-directional link and/or a directional link. Thecommunication interface 310 of the wireless device 110 may be configuredto communicate with the communication interface 320A of the base station1 120A and/or with the communication interface 320B of the base station2 120B. The base station 1 120A and the wireless device 110 and/or thebase station 2 120B and the wireless device 110 may be configured tosend and receive transport blocks via the wireless link 330A and/or viathe wireless link 330B, respectively. The wireless link 330A and/or thewireless link 330B may employ at least one frequency carrier. Accordingto some of various aspects of embodiments, transceiver(s) may beemployed. A transceiver may be a device that comprises both atransmitter and a receiver. Transceivers may be employed in devices suchas wireless devices, base stations, relay nodes, and/or the like.Example embodiments for radio technology implemented in thecommunication interface 310, 320A, 320B and the wireless link 330A, 330Bare illustrated in FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, FIG. 6, FIG. 7A,FIG. 7B, FIG. 8, and associated text.

In an example, other nodes in a wireless network (e.g. AMF, UPF, SMF,etc.) may comprise one or more communication interfaces, one or moreprocessors, and memory storing instructions.

A node (e.g. wireless device, base station, AMF, SMF, UPF, servers,switches, antennas, and/or the like) may comprise one or moreprocessors, and memory storing instructions that when executed by theone or more processors causes the node to perform certain processesand/or functions. Example embodiments may enable operation ofsingle-carrier and/or multi-carrier communications. Other exampleembodiments may comprise a non-transitory tangible computer readablemedia comprising instructions executable by one or more processors tocause operation of single-carrier and/or multi-carrier communications.Yet other example embodiments may comprise an article of manufacturethat comprises a non-transitory tangible computer readablemachine-accessible medium having instructions encoded thereon forenabling programmable hardware to cause a node to enable operation ofsingle-carrier and/or multi-carrier communications. The node may includeprocessors, memory, interfaces, and/or the like.

An interface may comprise at least one of a hardware interface, afirmware interface, a software interface, and/or a combination thereof.The hardware interface may comprise connectors, wires, electronicdevices such as drivers, amplifiers, and/or the like. The softwareinterface may comprise code stored in a memory device to implementprotocol(s), protocol layers, communication drivers, device drivers,combinations thereof, and/or the like. The firmware interface maycomprise a combination of embedded hardware and code stored in and/or incommunication with a memory device to implement connections, electronicdevice operations, protocol(s), protocol layers, communication drivers,device drivers, hardware operations, combinations thereof, and/or thelike.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure. FIG. 4A shows an example uplink transmitter forat least one physical channel. A baseband signal representing a physicaluplink shared channel may perform one or more functions. The one or morefunctions may comprise at least one of: scrambling; modulation ofscrambled bits to generate complex-valued symbols; mapping of thecomplex-valued modulation symbols onto one or several transmissionlayers; transform precoding to generate complex-valued symbols;precoding of the complex-valued symbols; mapping of precodedcomplex-valued symbols to resource elements; generation ofcomplex-valued time-domain Single Carrier-Frequency Division MultipleAccess (SC-FDMA) or CP-OFDM signal for an antenna port; and/or the like.In an example, when transform precoding is enabled, a SC-FDMA signal foruplink transmission may be generated. In an example, when transformprecoding is not enabled, an CP-OFDM signal for uplink transmission maybe generated by FIG. 4A. These functions are illustrated as examples andit is anticipated that other mechanisms may be implemented in variousembodiments.

An example structure for modulation and up-conversion to the carrierfrequency of the complex-valued SC-FDMA or CP-OFDM baseband signal foran antenna port and/or the complex-valued Physical Random Access CHannel(PRACH) baseband signal is shown in FIG. 4B. Filtering may be employedprior to transmission.

An example structure for downlink transmissions is shown in FIG. 4C. Thebaseband signal representing a downlink physical channel may perform oneor more functions. The one or more functions may comprise: scrambling ofcoded bits in a codeword to be transmitted on a physical channel;modulation of scrambled bits to generate complex-valued modulationsymbols; mapping of the complex-valued modulation symbols onto one orseveral transmission layers; precoding of the complex-valued modulationsymbols on a layer for transmission on the antenna ports; mapping ofcomplex-valued modulation symbols for an antenna port to resourceelements; generation of complex-valued time-domain OFDM signal for anantenna port; and/or the like. These functions are illustrated asexamples and it is anticipated that other mechanisms may be implementedin various embodiments.

In an example, a gNB may transmit a first symbol and a second symbol onan antenna port, to a wireless device. The wireless device may infer thechannel (e.g., fading gain, multipath delay, etc.) for conveying thesecond symbol on the antenna port, from the channel for conveying thefirst symbol on the antenna port. In an example, a first antenna portand a second antenna port may be quasi co-located if one or morelarge-scale properties of the channel over which a first symbol on thefirst antenna port is conveyed may be inferred from the channel overwhich a second symbol on a second antenna port is conveyed. The one ormore large-scale properties may comprise at least one of: delay spread;doppler spread; doppler shift; average gain; average delay; and/orspatial Receiving (Rx) parameters.

An example modulation and up-conversion to the carrier frequency of thecomplex-valued OFDM baseband signal for an antenna port is shown in FIG.4D. Filtering may be employed prior to transmission.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals. FIG. 5B is a diagram of an example downlinkchannel mapping and a downlink physical signals. In an example, aphysical layer may provide one or more information transfer services toa MAC and/or one or more higher layers. For example, the physical layermay provide the one or more information transfer services to the MAC viaone or more transport channels. An information transfer service mayindicate how and with what characteristics data are transferred over theradio interface.

In an example embodiment, a radio network may comprise one or moredownlink and/or uplink transport channels. For example, a diagram inFIG. 5A shows example uplink transport channels comprising Uplink-SharedCHannel (UL-SCH) 501 and Random Access CHannel (RACH) 502. A diagram inFIG. 5B shows example downlink transport channels comprisingDownlink-Shared CHannel (DL-SCH) 511, Paging CHannel (PCH) 512, andBroadcast CHannel (BCH) 513. A transport channel may be mapped to one ormore corresponding physical channels. For example, UL-SCH 501 may bemapped to Physical Uplink Shared CHannel (PUSCH) 503. RACH 502 may bemapped to PRACH 505. DL-SCH 511 and PCH 512 may be mapped to PhysicalDownlink Shared CHannel (PDSCH) 514. BCH 513 may be mapped to PhysicalBroadcast CHannel (PBCH) 516.

There may be one or more physical channels without a correspondingtransport channel. The one or more physical channels may be employed forUplink Control Information (UCI) 509 and/or Downlink Control Information(DCI) 517. For example, Physical Uplink Control CHannel (PUCCH) 504 maycarry UCI 509 from a UE to a base station. For example, PhysicalDownlink Control CHannel (PDCCH) 515 may carry DCI 517 from a basestation to a UE. NR may support UCI 509 multiplexing in PUSCH 503 whenUCI 509 and PUSCH 503 transmissions may coincide in a slot at least inpart. The UCI 509 may comprise at least one of CSI, Acknowledgement(ACK)/Negative Acknowledgement (NACK), and/or scheduling request. TheDCI 517 on PDCCH 515 may indicate at least one of following: one or moredownlink assignments and/or one or more uplink scheduling grants

In uplink, a UE may transmit one or more Reference Signals (RSs) to abase station. For example, the one or more RSs may be at least one ofDemodulation-RS (DM-RS) 506, Phase Tracking-RS (PT-RS) 507, and/orSounding RS (SRS) 508. In downlink, a base station may transmit (e.g.,unicast, multicast, and/or broadcast) one or more RSs to a UE. Forexample, the one or more RSs may be at least one of PrimarySynchronization Signal (PSS)/Secondary Synchronization Signal (SSS) 521,CSI-RS 522, DM-RS 523, and/or PT-RS 524.

In an example, a UE may transmit one or more uplink DM-RSs 506 to a basestation for channel estimation, for example, for coherent demodulationof one or more uplink physical channels (e.g., PUSCH 503 and/or PUCCH504). For example, a UE may transmit a base station at least one uplinkDM-RS 506 with PUSCH 503 and/or PUCCH 504, wherein the at least oneuplink DM-RS 506 may be spanning a same frequency range as acorresponding physical channel. In an example, a base station mayconfigure a UE with one or more uplink DM-RS configurations. At leastone DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). One or more additional uplink DM-RS may beconfigured to transmit at one or more symbols of a PUSCH and/or PUCCH. Abase station may semi-statistically configure a UE with a maximum numberof front-loaded DM-RS symbols for PUSCH and/or PUCCH. For example, a UEmay schedule a single-symbol DM-RS and/or double symbol DM-RS based on amaximum number of front-loaded DM-RS symbols, wherein a base station mayconfigure the UE with one or more additional uplink DM-RS for PUSCHand/or PUCCH. A new radio network may support, e.g., at least forCP-OFDM, a common DM-RS structure for DL and UL, wherein a DM-RSlocation, DM-RS pattern, and/or scrambling sequence may be same ordifferent.

In an example, whether uplink PT-RS 507 is present or not may depend ona RRC configuration. For example, a presence of uplink PT-RS may beUE-specifically configured. For example, a presence and/or a pattern ofuplink PT-RS 507 in a scheduled resource may be UE-specificallyconfigured by a combination of RRC signaling and/or association with oneor more parameters employed for other purposes (e.g., Modulation andCoding Scheme (MCS)) which may be indicated by DCI. When configured, adynamic presence of uplink PT-RS 507 may be associated with one or moreDCI parameters comprising at least MCS. A radio network may supportplurality of uplink PT-RS densities defined in time/frequency domain.When present, a frequency domain density may be associated with at leastone configuration of a scheduled bandwidth. A UE may assume a sameprecoding for a DMRS port and a PT-RS port. A number of PT-RS ports maybe fewer than a number of DM-RS ports in a scheduled resource. Forexample, uplink PT-RS 507 may be confined in the scheduledtime/frequency duration for a UE.

In an example, a UE may transmit SRS 508 to a base station for channelstate estimation to support uplink channel dependent scheduling and/orlink adaptation. For example, SRS 508 transmitted by a UE may allow fora base station to estimate an uplink channel state at one or moredifferent frequencies. A base station scheduler may employ an uplinkchannel state to assign one or more resource blocks of good quality foran uplink PUSCH transmission from a UE. A base station maysemi-statistically configure a UE with one or more SRS resource sets.For an SRS resource set, a base station may configure a UE with one ormore SRS resources. An SRS resource set applicability may be configuredby a higher layer (e.g., RRC) parameter. For example, when a higherlayer parameter indicates beam management, a SRS resource in each of oneor more SRS resource sets may be transmitted at a time instant. A UE maytransmit one or more SRS resources in different SRS resource setssimultaneously. A new radio network may support aperiodic, periodicand/or semi-persistent SRS transmissions. A UE may transmit SRSresources based on one or more trigger types, wherein the one or moretrigger types may comprise higher layer signaling (e.g., RRC) and/or oneor more DCI formats (e.g., at least one DCI format may be employed for aUE to select at least one of one or more configured SRS resource sets.An SRS trigger type 0 may refer to an SRS triggered based on a higherlayer signaling. An SRS trigger type 1 may refer to an SRS triggeredbased on one or more DCI formats. In an example, when PUSCH 503 and SRS508 are transmitted in a same slot, a UE may be configured to transmitSRS 508 after a transmission of PUSCH 503 and corresponding uplink DM-RS506.

In an example, a base station may semi-statistically configure a UE withone or more SRS configuration parameters indicating at least one offollowing: a SRS resource configuration identifier, a number of SRSports, time domain behavior of SRS resource configuration (e.g., anindication of periodic, semi-persistent, or aperiodic SRS), slot(mini-slot, and/or subframe) level periodicity and/or offset for aperiodic and/or aperiodic SRS resource, a number of OFDM symbols in aSRS resource, starting OFDM symbol of a SRS resource, a SRS bandwidth, afrequency hopping bandwidth, a cyclic shift, and/or a SRS sequence ID.

In an example, in a time domain, an SS/PBCH block may comprise one ormore OFDM symbols (e.g., 4 OFDM symbols numbered in increasing orderfrom 0 to 3) within the SS/PBCH block. An SS/PBCH block may comprisePSS/SSS 521 and PBCH 516. In an example, in the frequency domain, anSS/PBCH block may comprise one or more contiguous subcarriers (e.g., 240contiguous subcarriers with the subcarriers numbered in increasing orderfrom 0 to 239) within the SS/PBCH block. For example, a PSS/SSS 521 mayoccupy 1 OFDM symbol and 127 subcarriers. For example, PBCH 516 may spanacross 3 OFDM symbols and 240 subcarriers. A UE may assume that one ormore SS/PBCH blocks transmitted with a same block index may be quasico-located, e.g., with respect to Doppler spread, Doppler shift, averagegain, average delay, and spatial Rx parameters. A UE may not assumequasi co-location for other SS/PBCH block transmissions. A periodicityof an SS/PBCH block may be configured by a radio network (e.g., by anRRC signaling) and one or more time locations where the SS/PBCH blockmay be sent may be determined by sub-carrier spacing. In an example, aUE may assume a band-specific sub-carrier spacing for an SS/PBCH blockunless a radio network has configured a UE to assume a differentsub-carrier spacing.

In an example, downlink CSI-RS 522 may be employed for a UE to acquirechannel state information. A radio network may support periodic,aperiodic, and/or semi-persistent transmission of downlink CSI-RS 522.For example, a base station may semi-statistically configure and/orreconfigure a UE with periodic transmission of downlink CSI-RS 522. Aconfigured CSI-RS resources may be activated ad/or deactivated. Forsemi-persistent transmission, an activation and/or deactivation ofCSI-RS resource may be triggered dynamically. In an example, CSI-RSconfiguration may comprise one or more parameters indicating at least anumber of antenna ports. For example, a base station may configure a UEwith 32 ports. A base station may semi-statistically configure a UE withone or more CSI-RS resource sets. One or more CSI-RS resources may beallocated from one or more CSI-RS resource sets to one or more UEs. Forexample, a base station may semi-statistically configure one or moreparameters indicating CSI RS resource mapping, for example, time-domainlocation of one or more CSI-RS resources, a bandwidth of a CSI-RSresource, and/or a periodicity. In an example, a UE may be configured toemploy a same OFDM symbols for downlink CSI-RS 522 and control resourceset (coreset) when the downlink CSI-RS 522 and coreset are spatiallyquasi co-located and resource elements associated with the downlinkCSI-RS 522 are the outside of PRBs configured for coreset. In anexample, a UE may be configured to employ a same OFDM symbols fordownlink CSI-RS 522 and SSB/PBCH when the downlink CSI-RS 522 andSSB/PBCH are spatially quasi co-located and resource elements associatedwith the downlink CSI-RS 522 are the outside of PRBs configured forSSB/PBCH.

In an example, a UE may transmit one or more downlink DM-RSs 523 to abase station for channel estimation, for example, for coherentdemodulation of one or more downlink physical channels (e.g., PDSCH514). For example, a radio network may support one or more variableand/or configurable DM-RS patterns for data demodulation. At least onedownlink DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). A base station may semi-statisticallyconfigure a UE with a maximum number of front-loaded DM-RS symbols forPDSCH 514. For example, a DM-RS configuration may support one or moreDM-RS ports. For example, for single user-MIMO, a DM-RS configurationmay support at least 8 orthogonal downlink DM-RS ports. For example, formultiuser-MIMO, a DM-RS configuration may support 12 orthogonal downlinkDM-RS ports. A radio network may support, e.g., at least for CP-OFDM, acommon DM-RS structure for DL and UL, wherein a DM-RS location, DM-RSpattern, and/or scrambling sequence may be same or different.

In an example, whether downlink PT-RS 524 is present or not may dependon a RRC configuration. For example, a presence of downlink PT-RS 524may be UE-specifically configured. For example, a presence and/or apattern of downlink PT-RS 524 in a scheduled resource may beUE-specifically configured by a combination of RRC signaling and/orassociation with one or more parameters employed for other purposes(e.g., MCS) which may be indicated by DCI. When configured, a dynamicpresence of downlink PT-RS 524 may be associated with one or more DCIparameters comprising at least MCS. A radio network may supportplurality of PT-RS densities defined in time/frequency domain. Whenpresent, a frequency domain density may be associated with at least oneconfiguration of a scheduled bandwidth. A UE may assume a same precodingfor a DMRS port and a PT-RS port. A number of PT-RS ports may be fewerthan a number of DM-RS ports in a scheduled resource. For example,downlink PT-RS 524 may be confined in the scheduled time/frequencyduration for a UE.

FIG. 6 is a diagram depicting an example transmission time and receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure. A multicarrier OFDM communication system may include one ormore carriers, for example, ranging from 1 to 32 carriers, in case ofcarrier aggregation, or ranging from 1 to 64 carriers, in case of dualconnectivity. Different radio frame structures may be supported (e.g.,for FDD and for TDD duplex mechanisms). FIG. 6 shows an example frametiming. Downlink and uplink transmissions may be organized into radioframes 601. In this example, radio frame duration is 10 ms. In thisexample, a 10 ms radio frame 601 may be divided into ten equally sizedsubframes 602 with 1 ms duration. Subframe(s) may comprise one or moreslots (e.g. slots 603 and 605) depending on subcarrier spacing and/or CPlength. For example, a subframe with 15 kHz, 30 kHz, 60 kHz, 120 kHz,240 kHz and 480 kHz subcarrier spacing may comprise one, two, four,eight, sixteen and thirty-two slots, respectively. In FIG. 6, a subframemay be divided into two equally sized slots 603 with 0.5 ms duration.For example, 10 subframes may be available for downlink transmission and10 subframes may be available for uplink transmissions in a 10 msinterval. Uplink and downlink transmissions may be separated in thefrequency domain. Slot(s) may include a plurality of OFDM symbols 604.The number of OFDM symbols 604 in a slot 605 may depend on the cyclicprefix length. For example, a slot may be 14 OFDM symbols for the samesubcarrier spacing of up to 480 kHz with normal CP. A slot may be 12OFDM symbols for the same subcarrier spacing of 60 kHz with extended CP.A slot may contain downlink, uplink, or a downlink part and an uplinkpart and/or alike.

FIG. 7A is a diagram depicting example sets of OFDM subcarriers as peran aspect of an embodiment of the present disclosure. In the example, agNB may communicate with a wireless device with a carrier with anexample channel bandwidth 700. Arrow(s) in the diagram may depict asubcarrier in a multicarrier OFDM system. The OFDM system may usetechnology such as OFDM technology, SC-FDMA technology, and/or the like.In an example, an arrow 701 shows a subcarrier transmitting informationsymbols. In an example, a subcarrier spacing 702, between two contiguoussubcarriers in a carrier, may be any one of 15 KHz, 30 KHz, 60 KHz, 120KHz, 240 KHz etc. In an example, different subcarrier spacing maycorrespond to different transmission numerologies. In an example, atransmission numerology may comprise at least: a numerology index; avalue of subcarrier spacing; a type of cyclic prefix (CP). In anexample, a gNB may transmit to/receive from a UE on a number ofsubcarriers 703 in a carrier. In an example, a bandwidth occupied by anumber of subcarriers 703 (transmission bandwidth) may be smaller thanthe channel bandwidth 700 of a carrier, due to guard band 704 and 705.In an example, a guard band 704 and 705 may be used to reduceinterference to and from one or more neighbor carriers. A number ofsubcarriers (transmission bandwidth) in a carrier may depend on thechannel bandwidth of the carrier and the subcarrier spacing. Forexample, a transmission bandwidth, for a carrier with 20 MHz channelbandwidth and 15 KHz subcarrier spacing, may be in number of 1024subcarriers.

In an example, a gNB and a wireless device may communicate with multipleCCs when configured with CA. In an example, different component carriersmay have different bandwidth and/or subcarrier spacing, if CA issupported. In an example, a gNB may transmit a first type of service toa UE on a first component carrier. The gNB may transmit a second type ofservice to the UE on a second component carrier. Different type ofservices may have different service requirement (e.g., data rate,latency, reliability), which may be suitable for transmission viadifferent component carrier having different subcarrier spacing and/orbandwidth. FIG. 7B shows an example embodiment. A first componentcarrier may comprise a first number of subcarriers 706 with a firstsubcarrier spacing 709. A second component carrier may comprise a secondnumber of subcarriers 707 with a second subcarrier spacing 710. A thirdcomponent carrier may comprise a third number of subcarriers 708 with athird subcarrier spacing 711. Carriers in a multicarrier OFDMcommunication system may be contiguous carriers, non-contiguouscarriers, or a combination of both contiguous and non-contiguouscarriers.

FIG. 8 is a diagram depicting OFDM radio resources as per an aspect ofan embodiment of the present disclosure. In an example, a carrier mayhave a transmission bandwidth 801. In an example, a resource grid may bein a structure of frequency domain 802 and time domain 803. In anexample, a resource grid may comprise a first number of OFDM symbols ina subframe and a second number of resource blocks, starting from acommon resource block indicated by higher-layer signaling (e.g. RRCsignaling), for a transmission numerology and a carrier. In an example,in a resource grid, a resource unit identified by a subcarrier index anda symbol index may be a resource element 805. In an example, a subframemay comprise a first number of OFDM symbols 807 depending on anumerology associated with a carrier. For example, when a subcarrierspacing of a numerology of a carrier is 15 KHz, a subframe may have 14OFDM symbols for a carrier. When a subcarrier spacing of a numerology is30 KHz, a subframe may have 28 OFDM symbols. When a subcarrier spacingof a numerology is 60 Khz, a subframe may have 56 OFDM symbols, etc. Inan example, a second number of resource blocks comprised in a resourcegrid of a carrier may depend on a bandwidth and a numerology of thecarrier.

As shown in FIG. 8, a resource block 806 may comprise 12 subcarriers. Inan example, multiple resource blocks may be grouped into a ResourceBlock Group (RBG) 804. In an example, a size of a RBG may depend on atleast one of: a RRC message indicating a RBG size configuration; a sizeof a carrier bandwidth; or a size of a bandwidth part of a carrier. Inan example, a carrier may comprise multiple bandwidth parts. A firstbandwidth part of a carrier may have different frequency location and/orbandwidth from a second bandwidth part of the carrier.

In an example, a gNB may transmit a downlink control informationcomprising a downlink or uplink resource block assignment to a wirelessdevice. A base station may transmit to or receive from, a wirelessdevice, data packets (e.g. transport blocks) scheduled and transmittedvia one or more resource blocks and one or more slots according toparameters in a downlink control information and/or RRC message(s). Inan example, a starting symbol relative to a first slot of the one ormore slots may be indicated to the wireless device. In an example, a gNBmay transmit to or receive from, a wireless device, data packetsscheduled on one or more RBGs and one or more slots.

In an example, a gNB may transmit a downlink control informationcomprising a downlink assignment to a wireless device via one or morePDCCHs. The downlink assignment may comprise parameters indicating atleast modulation and coding format; resource allocation; and/or HARQinformation related to DL-SCH. In an example, a resource allocation maycomprise parameters of resource block allocation; and/or slotallocation. In an example, a gNB may dynamically allocate resources to awireless device via a Cell-Radio Network Temporary Identifier (C-RNTI)on one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible allocation when its downlink receptionis enabled. The wireless device may receive one or more downlink datapackage on one or more PDSCH scheduled by the one or more PDCCHs, whensuccessfully detecting the one or more PDCCHs.

In an example, a gNB may allocate Configured Scheduling (CS) resourcesfor down link transmission to a wireless device. The gNB may transmitone or more RRC messages indicating a periodicity of the CS grant. ThegNB may transmit a DCI via a PDCCH addressed to a ConfiguredScheduling-RNTI (CS-RNTI) activating the CS resources. The DCI maycomprise parameters indicating that the downlink grant is a CS grant.The CS grant may be implicitly reused according to the periodicitydefined by the one or more RRC messages, until deactivated.

In an example, a gNB may transmit a downlink control informationcomprising an uplink grant to a wireless device via one or more PDCCHs.The uplink grant may comprise parameters indicating at least modulationand coding format; resource allocation; and/or HARQ information relatedto UL-SCH. In an example, a resource allocation may comprise parametersof resource block allocation; and/or slot allocation. In an example, agNB may dynamically allocate resources to a wireless device via a C-RNTIon one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible resource allocation. The wirelessdevice may transmit one or more uplink data package via one or morePUSCH scheduled by the one or more PDCCHs, when successfully detectingthe one or more PDCCHs.

In an example, a gNB may allocate CS resources for uplink datatransmission to a wireless device. The gNB may transmit one or more RRCmessages indicating a periodicity of the CS grant. The gNB may transmita DCI via a PDCCH addressed to a CS-RNTI activating the CS resources.The DCI may comprise parameters indicating that the uplink grant is a CSgrant. The CS grant may be implicitly reused according to theperiodicity defined by the one or more RRC message, until deactivated.

In an example, a base station may transmit DCI/control signaling viaPDCCH. The DCI may take a format in a plurality of formats. A DCI maycomprise downlink and/or uplink scheduling information (e.g., resourceallocation information, HARQ related parameters, MCS), request for CSI(e.g., aperiodic CQI reports), request for SRS, uplink power controlcommands for one or more cells, one or more timing information (e.g., TBtransmission/reception timing, HARQ feedback timing, etc.), etc. In anexample, a DCI may indicate an uplink grant comprising transmissionparameters for one or more transport blocks. In an example, a DCI mayindicate downlink assignment indicating parameters for receiving one ormore transport blocks. In an example, a DCI may be used by base stationto initiate a contention-free random access at the wireless device. Inan example, the base station may transmit a DCI comprising slot formatindicator (SFI) notifying a slot format. In an example, the base stationmay transmit a DCI comprising pre-emption indication notifying thePRB(s) and/or OFDM symbol(s) where a UE may assume no transmission isintended for the UE. In an example, the base station may transmit a DCIfor group power control of PUCCH or PUSCH or SRS. In an example, a DCImay correspond to an RNTI. In an example, the wireless device may obtainan RNTI in response to completing the initial access (e.g., C-RNTI). Inan example, the base station may configure an RNTI for the wireless(e.g., CS-RNTI, TPC-CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI,TPC-SRS-RNTI). In an example, the wireless device may compute an RNTI(e.g., the wireless device may compute RA-RNTI based on resources usedfor transmission of a preamble). In an example, an RNTI may have apre-configured value (e.g., P-RNTI or SI-RNTI). In an example, awireless device may monitor a group common search space which may beused by base station for transmitting DCIs that are intended for a groupof UEs. In an example, a group common DCI may correspond to an RNTIwhich is commonly configured for a group of UEs. In an example, awireless device may monitor a UE-specific search space. In an example, aUE specific DCI may correspond to an RNTI configured for the wirelessdevice.

A NR system may support a single beam operation and/or a multi-beamoperation. In a multi-beam operation, a base station may perform adownlink beam sweeping to provide coverage for common control channelsand/or downlink SS blocks, which may comprise at least a PSS, a SSS,and/or PBCH. A wireless device may measure quality of a beam pair linkusing one or more RSs. One or more SS blocks, or one or more CSI-RSresources, associated with a CSI-RS resource index (CRI), or one or moreDM-RSs of PBCH, may be used as RS for measuring quality of a beam pairlink. Quality of a beam pair link may be defined as a reference signalreceived power (RSRP) value, or a reference signal received quality(RSRQ) value, and/or a CSI value measured on RS resources. The basestation may indicate whether an RS resource, used for measuring a beampair link quality, is quasi-co-located (QCLed) with DM-RSs of a controlchannel. A RS resource and DM-RSs of a control channel may be calledQCLed when a channel characteristics from a transmission on an RS to awireless device, and that from a transmission on a control channel to awireless device, are similar or same under a configured criterion. In amulti-beam operation, a wireless device may perform an uplink beamsweeping to access a cell.

In an example, a wireless device may be configured to monitor PDCCH onone or more beam pair links simultaneously depending on a capability ofa wireless device. This may increase robustness against beam pair linkblocking. A base station may transmit one or more messages to configurea wireless device to monitor PDCCH on one or more beam pair links indifferent PDCCH OFDM symbols. For example, a base station may transmithigher layer signaling (e.g. RRC signaling) or MAC CE comprisingparameters related to the Rx beam setting of a wireless device formonitoring PDCCH on one or more beam pair links. A base station maytransmit indication of spatial QCL assumption between an DL RS antennaport(s) (for example, cell-specific CSI-RS, or wireless device-specificCSI-RS, or SS block, or PBCH with or without DM-RSs of PBCH), and DL RSantenna port(s) for demodulation of DL control channel. Signaling forbeam indication for a PDCCH may be MAC CE signaling, or RRC signaling,or DCI signaling, or specification-transparent and/or implicit method,and combination of these signaling methods.

For reception of unicast DL data channel, a base station may indicatespatial QCL parameters between DL RS antenna port(s) and DM-RS antennaport(s) of DL data channel. The base station may transmit DCI (e.g.downlink grants) comprising information indicating the RS antennaport(s). The information may indicate RS antenna port(s) which may beQCL-ed with the DM-RS antenna port(s). Different set of DM-RS antennaport(s) for a DL data channel may be indicated as QCL with different setof the RS antenna port(s).

FIG. 9A is an example of beam sweeping in a DL channel. In anRRC_INACTIVE state or RRC_IDLE state, a wireless device may assume thatSS blocks form an SS burst 940, and an SS burst set 950. The SS burstset 950 may have a given periodicity. For example, in a multi-beamoperation, a base station 120 may transmit SS blocks in multiple beams,together forming a SS burst 940. One or more SS blocks may betransmitted on one beam. If multiple SS bursts 940 are transmitted withmultiple beams, SS bursts together may form SS burst set 950.

A wireless device may further use CSI-RS in the multi-beam operation forestimating a beam quality of a links between a wireless device and abase station. A beam may be associated with a CSI-RS. For example, awireless device may, based on a RSRP measurement on CSI-RS, report abeam index, as indicated in a CRI for downlink beam selection, andassociated with a RSRP value of a beam. A CSI-RS may be transmitted on aCSI-RS resource including at least one of one or more antenna ports, oneor more time or frequency radio resources. A CSI-RS resource may beconfigured in a cell-specific way by common RRC signaling, or in awireless device-specific way by dedicated RRC signaling, and/or L1/L2signaling. Multiple wireless devices covered by a cell may measure acell-specific CSI-RS resource. A dedicated subset of wireless devicescovered by a cell may measure a wireless device-specific CSI-RSresource.

A CSI-RS resource may be transmitted periodically, or using aperiodictransmission, or using a multi-shot or semi-persistent transmission. Forexample, in a periodic transmission in FIG. 9A, a base station 120 maytransmit configured CSI-RS resources 940 periodically using a configuredperiodicity in a time domain. In an aperiodic transmission, a configuredCSI-RS resource may be transmitted in a dedicated time slot. In amulti-shot or semi-persistent transmission, a configured CSI-RS resourcemay be transmitted within a configured period. Beams used for CSI-RStransmission may have different beam width than beams used for SS-blockstransmission.

FIG. 9B is an example of a beam management procedure in an example newradio network. A base station 120 and/or a wireless device 110 mayperform a downlink L1/L2 beam management procedure. One or more of thefollowing downlink L1/L2 beam management procedures may be performedwithin one or more wireless devices 110 and one or more base stations120. In an example, a P-1 procedure 910 may be used to enable thewireless device 110 to measure one or more Transmission (Tx) beamsassociated with the base station 120 to support a selection of a firstset of Tx beams associated with the base station 120 and a first set ofRx beam(s) associated with a wireless device 110. For beamforming at abase station 120, a base station 120 may sweep a set of different TXbeams. For beamforming at a wireless device 110, a wireless device 110may sweep a set of different Rx beams. In an example, a P-2 procedure920 may be used to enable a wireless device 110 to measure one or moreTx beams associated with a base station 120 to possibly change a firstset of Tx beams associated with a base station 120. A P-2 procedure 920may be performed on a possibly smaller set of beams for beam refinementthan in the P-1 procedure 910. A P-2 procedure 920 may be a special caseof a P-1 procedure 910. In an example, a P-3 procedure 930 may be usedto enable a wireless device 110 to measure at least one Tx beamassociated with a base station 120 to change a first set of Rx beamsassociated with a wireless device 110.

A wireless device 110 may transmit one or more beam management reportsto a base station 120. In one or more beam management reports, awireless device 110 may indicate some beam pair quality parameters,comprising at least, one or more beam identifications; RSRP; PrecodingMatrix Indicator (PMI)/Channel Quality Indicator (CQI)/Rank Indicator(RI) of a subset of configured beams. Based on one or more beammanagement reports, a base station 120 may transmit to a wireless device110 a signal indicating that one or more beam pair links are one or moreserving beams. A base station 120 may transmit PDCCH and PDSCH for awireless device 110 using one or more serving beams.

In an example embodiment, new radio network may support a BandwidthAdaptation (BA). In an example, receive and/or transmit bandwidthsconfigured by an UE employing a BA may not be large. For example, areceive and/or transmit bandwidths may not be as large as a bandwidth ofa cell. Receive and/or transmit bandwidths may be adjustable. Forexample, a UE may change receive and/or transmit bandwidths, e.g., toshrink during period of low activity to save power. For example, a UEmay change a location of receive and/or transmit bandwidths in afrequency domain, e.g. to increase scheduling flexibility. For example,a UE may change a subcarrier spacing, e.g. to allow different services.

In an example embodiment, a subset of a total cell bandwidth of a cellmay be referred to as a Bandwidth Part (BWP). A base station mayconfigure a UE with one or more BWPs to achieve a BA. For example, abase station may indicate, to a UE, which of the one or more(configured) BWPs is an active BWP.

FIG. 10 is an example diagram of 3 BWPs configured: BWP1 (1010 and 1050)with a width of 40 MHz and subcarrier spacing of 15 kHz; BWP2 (1020 and1040) with a width of 10 MHz and subcarrier spacing of 15 kHz; BWP3 1030with a width of 20 MHz and subcarrier spacing of 60 kHz.

In an example, a UE, configured for operation in one or more BWPs of acell, may be configured by one or more higher layers (e.g. RRC layer)for a cell a set of one or more BWPs (e.g., at most four BWPs) forreceptions by the UE (DL BWP set) in a DL bandwidth by at least oneparameter DL-BWP and a set of one or more BWPs (e.g., at most four BWPs)for transmissions by a UE (UL BWP set) in an UL bandwidth by at leastone parameter UL-BWP for a cell.

To enable BA on the PCell, a base station may configure a UE with one ormore UL and DL BWP pairs. To enable BA on SCells (e.g., in case of CA),a base station may configure a UE at least with one or more DL BWPs(e.g., there may be none in an UL).

In an example, an initial active DL BWP may be defined by at least oneof a location and number of contiguous PRBs, a subcarrier spacing, or acyclic prefix, for a control resource set for at least one common searchspace. For operation on the PCell, one or more higher layer parametersmay indicate at least one initial UL BWP for a random access procedure.If a UE is configured with a secondary carrier on a primary cell, the UEmay be configured with an initial BWP for random access procedure on asecondary carrier.

In an example, for unpaired spectrum operation, a UE may expect that acenter frequency for a DL BWP may be same as a center frequency for a ULBWP.

For example, for a DL BWP or an UL BWP in a set of one or more DL BWPsor one or more UL BWPs, respectively, a base statin maysemi-statistically configure a UE for a cell with one or more parametersindicating at least one of following: a subcarrier spacing; a cyclicprefix; a number of contiguous PRBs; an index in the set of one or moreDL BWPs and/or one or more UL BWPs; a link between a DL BWP and an ULBWP from a set of configured DL BWPs and UL BWPs; a DCI detection to aPDSCH reception timing; a PDSCH reception to a HARQ-ACK transmissiontiming value; a DCI detection to a PUSCH transmission timing value; anoffset of a first PRB of a DL bandwidth or an UL bandwidth,respectively, relative to a first PRB of a bandwidth.

In an example, for a DL BWP in a set of one or more DL BWPs on a PCell,a base station may configure a UE with one or more control resource setsfor at least one type of common search space and/or one UE-specificsearch space. For example, a base station may not configure a UE withouta common search space on a PCell, or on a PSCell, in an active DL BWP.

For an UL BWP in a set of one or more UL BWPs, a base station mayconfigure a UE with one or more resource sets for one or more PUCCHtransmissions.

In an example, if a DCI comprises a BWP indicator field, a BWP indicatorfield value may indicate an active DL BWP, from a configured DL BWP set,for one or more DL receptions. If a DCI comprises a BWP indicator field,a BWP indicator field value may indicate an active UL BWP, from aconfigured UL BWP set, for one or more UL transmissions.

In an example, for a PCell, a base station may semi-statisticallyconfigure a UE with a default DL BWP among configured DL BWPs. If a UEis not provided a default DL BWP, a default BWP may be an initial activeDL BWP.

In an example, a base station may configure a UE with a timer value fora PCell. For example, a UE may start a timer, referred to as BWPinactivity timer, when a UE detects a DCI indicating an active DL BWP,other than a default DL BWP, for a paired spectrum operation or when aUE detects a DCI indicating an active DL BWP or UL BWP, other than adefault DL BWP or UL BWP, for an unpaired spectrum operation. The UE mayincrement the timer by an interval of a first value (e.g., the firstvalue may be 1 millisecond or 0.5 milliseconds) if the UE does notdetect a DCI during the interval for a paired spectrum operation or foran unpaired spectrum operation. In an example, the timer may expire whenthe timer is equal to the timer value. A UE may switch to the default DLBWP from an active DL BWP when the timer expires.

In an example, a base station may semi-statistically configure a UE withone or more BWPs. A UE may switch an active BWP from a first BWP to asecond BWP in response to receiving a DCI indicating the second BWP asan active BWP and/or in response to an expiry of BWP inactivity timer(for example, the second BWP may be a default BWP). For example, FIG. 10is an example diagram of 3 BWPs configured, BWP1 (1010 and 1050), BWP2(1020 and 1040), and BWP3 (1030). BWP2 (1020 and 1040) may be a defaultBWP. BWP1 (1010) may be an initial active BWP. In an example, a UE mayswitch an active BWP from BWP1 1010 to BWP2 1020 in response to anexpiry of BWP inactivity timer. For example, a UE may switch an activeBWP from BWP2 1020 to BWP3 1030 in response to receiving a DCIindicating BWP3 1030 as an active BWP. Switching an active BWP from BWP31030 to BWP2 1040 and/or from BWP2 1040 to BWP1 1050 may be in responseto receiving a DCI indicating an active BWP and/or in response to anexpiry of BWP inactivity timer.

In an example, if a UE is configured for a secondary cell with a defaultDL BWP among configured DL BWPs and a timer value, UE procedures on asecondary cell may be same as on a primary cell using the timer valuefor the secondary cell and the default DL BWP for the secondary cell.

In an example, if a base station configures a UE with a first active DLBWP and a first active UL BWP on a secondary cell or carrier, a UE mayemploy an indicated DL BWP and an indicated UL BWP on a secondary cellas a respective first active DL BWP and first active UL BWP on asecondary cell or carrier.

FIG. 11A and FIG. 11B show packet flows employing a multi connectivity(e.g. dual connectivity, multi connectivity, tight interworking, and/orthe like). FIG. 11A is an example diagram of a protocol structure of awireless device 110 (e.g. UE) with CA and/or multi connectivity as peran aspect of an embodiment. FIG. 11B is an example diagram of a protocolstructure of multiple base stations with CA and/or multi connectivity asper an aspect of an embodiment. The multiple base stations may comprisea master node, MN 1130 (e.g. a master node, a master base station, amaster gNB, a master eNB, and/or the like) and a secondary node, SN 1150(e.g. a secondary node, a secondary base station, a secondary gNB, asecondary eNB, and/or the like). A master node 1130 and a secondary node1150 may co-work to communicate with a wireless device 110.

When multi connectivity is configured for a wireless device 110, thewireless device 110, which may support multiple reception/transmissionfunctions in an RRC connected state, may be configured to utilize radioresources provided by multiple schedulers of a multiple base stations.Multiple base stations may be inter-connected via a non-ideal or idealbackhaul (e.g. Xn interface, X2 interface, and/or the like). A basestation involved in multi connectivity for a certain wireless device mayperform at least one of two different roles: a base station may eitheract as a master base station or as a secondary base station. In multiconnectivity, a wireless device may be connected to one master basestation and one or more secondary base stations. In an example, a masterbase station (e.g. the MN 1130) may provide a master cell group (MCG)comprising a primary cell and/or one or more secondary cells for awireless device (e.g. the wireless device 110). A secondary base station(e.g. the SN 1150) may provide a secondary cell group (SCG) comprising aprimary secondary cell (PSCell) and/or one or more secondary cells for awireless device (e.g. the wireless device 110).

In multi connectivity, a radio protocol architecture that a beareremploys may depend on how a bearer is setup. In an example, threedifferent type of bearer setup options may be supported: an MCG bearer,an SCG bearer, and/or a split bearer. A wireless device mayreceive/transmit packets of an MCG bearer via one or more cells of theMCG, and/or may receive/transmits packets of an SCG bearer via one ormore cells of an SCG. Multi-connectivity may also be described as havingat least one bearer configured to use radio resources provided by thesecondary base station. Multi-connectivity may or may not beconfigured/implemented in some of the example embodiments.

In an example, a wireless device (e.g. Wireless Device 110) may transmitand/or receive: packets of an MCG bearer via an SDAP layer (e.g. SDAP1110), a PDCP layer (e.g. NR PDCP 1111), an RLC layer (e.g. MN RLC1114), and a MAC layer (e.g. MN MAC 1118); packets of a split bearer viaan SDAP layer (e.g. SDAP 1110), a PDCP layer (e.g. NR PDCP 1112), one ofa master or secondary RLC layer (e.g. MN RLC 1115, SN RLC 1116), and oneof a master or secondary MAC layer (e.g. MN MAC 1118, SN MAC 1119);and/or packets of an SCG bearer via an SDAP layer (e.g. SDAP 1110), aPDCP layer (e.g. NR PDCP 1113), an RLC layer (e.g. SN RLC 1117), and aMAC layer (e.g. MN MAC 1119).

In an example, a master base station (e.g. MN 1130) and/or a secondarybase station (e.g. SN 1150) may transmit/receive: packets of an MCGbearer via a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP1140), a master or secondary node PDCP layer (e.g. NR PDCP 1121, NR PDCP1142), a master node RLC layer (e.g. MN RLC 1124, MN RLC 1125), and amaster node MAC layer (e.g. MN MAC 1128); packets of an SCG bearer via amaster or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1122, NR PDCP 1143), asecondary node RLC layer (e.g. SN RLC 1146, SN RLC 1147), and asecondary node MAC layer (e.g. SN MAC 1148); packets of a split bearervia a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1123, NR PDCP 1141), amaster or secondary node RLC layer (e.g. MN RLC 1126, SN RLC 1144, SNRLC 1145, MN RLC 1127), and a master or secondary node MAC layer (e.g.MN MAC 1128, SN MAC 1148).

In multi connectivity, a wireless device may configure multiple MACentities: one MAC entity (e.g. MN MAC 1118) for a master base station,and other MAC entities (e.g. SN MAC 1119) for a secondary base station.In multi-connectivity, a configured set of serving cells for a wirelessdevice may comprise two subsets: an MCG comprising serving cells of amaster base station, and SCGs comprising serving cells of a secondarybase station. For an SCG, one or more of following configurations may beapplied: at least one cell of an SCG has a configured UL CC and at leastone cell of a SCG, named as primary secondary cell (PSCell, PCell ofSCG, or sometimes called PCell), is configured with PUCCH resources;when an SCG is configured, there may be at least one SCG bearer or oneSplit bearer; upon detection of a physical layer problem or a randomaccess problem on a PSCell, or a number of NR RLC retransmissions hasbeen reached associated with the SCG, or upon detection of an accessproblem on a PSCell during a SCG addition or a SCG change: an RRCconnection re-establishment procedure may not be triggered, ULtransmissions towards cells of an SCG may be stopped, a master basestation may be informed by a wireless device of a SCG failure type, forsplit bearer, a DL data transfer over a master base station may bemaintained; an NR RLC acknowledged mode (AM) bearer may be configuredfor a split bearer; PCell and/or PSCell may not be de-activated; PSCellmay be changed with a SCG change procedure (e.g. with security keychange and a RACH procedure); and/or a bearer type change between asplit bearer and a SCG bearer or simultaneous configuration of a SCG anda split bearer may or may not supported.

With respect to interaction between a master base station and asecondary base stations for multi-connectivity, one or more of thefollowing may be applied: a master base station and/or a secondary basestation may maintain RRM measurement configurations of a wirelessdevice; a master base station may (e.g. based on received measurementreports, traffic conditions, and/or bearer types) may decide to requesta secondary base station to provide additional resources (e.g. servingcells) for a wireless device; upon receiving a request from a masterbase station, a secondary base station may create/modify a containerthat may result in configuration of additional serving cells for awireless device (or decide that the secondary base station has noresource available to do so); for a UE capability coordination, a masterbase station may provide (a part of) an AS configuration and UEcapabilities to a secondary base station; a master base station and asecondary base station may exchange information about a UE configurationby employing of RRC containers (inter-node messages) carried via Xnmessages; a secondary base station may initiate a reconfiguration of thesecondary base station existing serving cells (e.g. PUCCH towards thesecondary base station); a secondary base station may decide which cellis a PSCell within a SCG; a master base station may or may not changecontent of RRC configurations provided by a secondary base station; incase of a SCG addition and/or a SCG SCell addition, a master basestation may provide recent (or the latest) measurement results for SCGcell(s); a master base station and secondary base stations may receiveinformation of SFN and/or subframe offset of each other from OAM and/orvia an Xn interface, (e.g. for a purpose of DRX alignment and/oridentification of a measurement gap). In an example, when adding a newSCG SCell, dedicated RRC signaling may be used for sending requiredsystem information of a cell as for CA, except for a SFN acquired from aMIB of a PSCell of a SCG.

FIG. 12 is an example diagram of a random access procedure. One or moreevents may trigger a random access procedure. For example, one or moreevents may be at least one of following: initial access from RRC_IDLE,RRC connection re-establishment procedure, handover, DL or UL dataarrival during RRC_CONNECTED when UL synchronization status isnon-synchronized, transition from RRC_Inactive, and/or request for othersystem information. For example, a PDCCH order, a MAC entity, and/or abeam failure indication may initiate a random access procedure.

In an example embodiment, a random access procedure may be at least oneof a contention based random access procedure and a contention freerandom access procedure. For example, a contention based random accessprocedure may comprise, one or more Msg 1 1220 transmissions, one ormore Msg2 1230 transmissions, one or more Msg3 1240 transmissions, andcontention resolution 1250. For example, a contention free random accessprocedure may comprise one or more Msg 1 1220 transmissions and one ormore Msg2 1230 transmissions.

In an example, a base station may transmit (e.g., unicast, multicast, orbroadcast), to a UE, a RACH configuration 1210 via one or more beams.The RACH configuration 1210 may comprise one or more parametersindicating at least one of following: available set of PRACH resourcesfor a transmission of a random access preamble, initial preamble power(e.g., random access preamble initial received target power), an RSRPthreshold for a selection of a SS block and corresponding PRACHresource, a power-ramping factor (e.g., random access preamble powerramping step), random access preamble index, a maximum number ofpreamble transmission, preamble group A and group B, a threshold (e.g.,message size) to determine the groups of random access preambles, a setof one or more random access preambles for system information requestand corresponding PRACH resource(s), if any, a set of one or more randomaccess preambles for beam failure recovery request and correspondingPRACH resource(s), if any, a time window to monitor RA response(s), atime window to monitor response(s) on beam failure recovery request,and/or a contention resolution timer.

In an example, the Msg1 1220 may be one or more transmissions of arandom access preamble. For a contention based random access procedure,a UE may select a SS block with a RSRP above the RSRP threshold. Ifrandom access preambles group B exists, a UE may select one or morerandom access preambles from a group A or a group B depending on apotential Msg3 1240 size. If a random access preambles group B does notexist, a UE may select the one or more random access preambles from agroup A. A UE may select a random access preamble index randomly (e.g.with equal probability or a normal distribution) from one or more randomaccess preambles associated with a selected group. If a base stationsemi-statistically configures a UE with an association between randomaccess preambles and SS blocks, the UE may select a random accesspreamble index randomly with equal probability from one or more randomaccess preambles associated with a selected SS block and a selectedgroup.

For example, a UE may initiate a contention free random access procedurebased on a beam failure indication from a lower layer. For example, abase station may semi-statistically configure a UE with one or morecontention free PRACH resources for beam failure recovery requestassociated with at least one of SS blocks and/or CSI-RSs. If at leastone of SS blocks with a RSRP above a first RSRP threshold amongstassociated SS blocks or at least one of CSI-RSs with a RSRP above asecond RSRP threshold amongst associated CSI-RSs is available, a UE mayselect a random access preamble index corresponding to a selected SSblock or CSI-RS from a set of one or more random access preambles forbeam failure recovery request.

For example, a UE may receive, from a base station, a random accesspreamble index via PDCCH or RRC for a contention free random accessprocedure. If a base station does not configure a UE with at least onecontention free PRACH resource associated with SS blocks or CSI-RS, theUE may select a random access preamble index. If a base stationconfigures a UE with one or more contention free PRACH resourcesassociated with SS blocks and at least one SS block with a RSRP above afirst RSRP threshold amongst associated SS blocks is available, the UEmay select the at least one SS block and select a random access preamblecorresponding to the at least one SS block. If a base station configuresa UE with one or more contention free PRACH resources associated withCSI-RSs and at least one CSI-RS with a RSRP above a second RSPRthreshold amongst the associated CSI-RSs is available, the UE may selectthe at least one CSI-RS and select a random access preamblecorresponding to the at least one CSI-RS.

A UE may perform one or more Msg1 1220 transmissions by transmitting theselected random access preamble. For example, if a UE selects an SSblock and is configured with an association between one or more PRACHoccasions and one or more SS blocks, the UE may determine an PRACHoccasion from one or more PRACH occasions corresponding to a selected SSblock. For example, if a UE selects a CSI-RS and is configured with anassociation between one or more PRACH occasions and one or more CSI-RSs,the UE may determine a PRACH occasion from one or more PRACH occasionscorresponding to a selected CSI-RS. A UE may transmit, to a basestation, a selected random access preamble via a selected PRACHoccasions. A UE may determine a transmit power for a transmission of aselected random access preamble at least based on an initial preamblepower and a power-ramping factor. A UE may determine a RA-RNTIassociated with a selected PRACH occasions in which a selected randomaccess preamble is transmitted. For example, a UE may not determine aRA-RNTI for a beam failure recovery request. A UE may determine anRA-RNTI at least based on an index of a first OFDM symbol and an indexof a first slot of a selected PRACH occasions, and/or an uplink carrierindex for a transmission of Msg1 1220.

In an example, a UE may receive, from a base station, a random accessresponse, Msg 2 1230. A UE may start a time window (e.g.,ra-ResponseWindow) to monitor a random access response. For beam failurerecovery request, a base station may configure a UE with a differenttime window (e.g., bfr-Response Window) to monitor response on beamfailure recovery request. For example, a UE may start a time window(e.g., ra-ResponseWindow or bfr-ResponseWindow) at a start of a firstPDCCH occasion after a fixed duration of one or more symbols from an endof a preamble transmission. If a UE transmits multiple preambles, the UEmay start a time window at a start of a first PDCCH occasion after afixed duration of one or more symbols from an end of a first preambletransmission. A UE may monitor a PDCCH of a cell for at least one randomaccess response identified by a RA-RNTI or for at least one response tobeam failure recovery request identified by a C-RNTI while a timer for atime window is running.

In an example, a UE may consider a reception of random access responsesuccessful if at least one random access response comprises a randomaccess preamble identifier corresponding to a random access preambletransmitted by the UE. A UE may consider the contention free randomaccess procedure successfully completed if a reception of random accessresponse is successful. If a contention free random access procedure istriggered for a beam failure recovery request, a UE may consider acontention free random access procedure successfully complete if a PDCCHtransmission is addressed to a C-RNTI. In an example, if at least onerandom access response comprises a random access preamble identifier, aUE may consider the random access procedure successfully completed andmay indicate a reception of an acknowledgement for a system informationrequest to upper layers. If a UE has signaled multiple preambletransmissions, the UE may stop transmitting remaining preambles (if any)in response to a successful reception of a corresponding random accessresponse.

In an example, a UE may perform one or more Msg 3 1240 transmissions inresponse to a successful reception of random access response (e.g., fora contention based random access procedure). A UE may adjust an uplinktransmission timing based on a timing advanced command indicated by arandom access response and may transmit one or more transport blocksbased on an uplink grant indicated by a random access response.Subcarrier spacing for PUSCH transmission for Msg3 1240 may be providedby at least one higher layer (e.g. RRC) parameter. A UE may transmit arandom access preamble via PRACH and Msg3 1240 via PUSCH on a same cell.A base station may indicate an UL BWP for a PUSCH transmission of Msg31240 via system information block. A UE may employ HARQ for aretransmission of Msg 3 1240.

In an example, multiple UEs may perform Msg 1 1220 by transmitting asame preamble to a base station and receive, from the base station, asame random access response comprising an identity (e.g., TC-RNTI).Contention resolution 1250 may ensure that a UE does not incorrectly usean identity of another UE. For example, contention resolution 1250 maybe based on C-RNTI on PDCCH or a UE contention resolution identity onDL-SCH. For example, if a base station assigns a C-RNTI to a UE, the UEmay perform contention resolution 1250 based on a reception of a PDCCHtransmission that is addressed to the C-RNTI. In response to detectionof a C-RNTI on a PDCCH, a UE may consider contention resolution 1250successful and may consider a random access procedure successfullycompleted. If a UE has no valid C-RNTI, a contention resolution may beaddressed by employing a TC-RNTI. For example, if a MAC PDU issuccessfully decoded and a MAC PDU comprises a UE contention resolutionidentity MAC CE that matches the CCCH SDU transmitted in Msg3 1250, a UEmay consider the contention resolution 1250 successful and may considerthe random access procedure successfully completed.

FIG. 13 is an example structure for MAC entities as per an aspect of anembodiment. In an example, a wireless device may be configured tooperate in a multi-connectivity mode. A wireless device in RRC_CONNECTEDwith multiple RX/TX may be configured to utilize radio resourcesprovided by multiple schedulers located in a plurality of base stations.The plurality of base stations may be connected via a non-ideal or idealbackhaul over the Xn interface. In an example, a base station in aplurality of base stations may act as a master base station or as asecondary base station. A wireless device may be connected to one masterbase station and one or more secondary base stations. A wireless devicemay be configured with multiple MAC entities, e.g. one MAC entity formaster base station, and one or more other MAC entities for secondarybase station(s). In an example, a configured set of serving cells for awireless device may comprise two subsets: an MCG comprising servingcells of a master base station, and one or more SCGs comprising servingcells of a secondary base station(s). FIG. 13 illustrates an examplestructure for MAC entities when MCG and SCG are configured for awireless device.

In an example, at least one cell in a SCG may have a configured UL CC,wherein a cell of at least one cell may be called PSCell or PCell ofSCG, or sometimes may be simply called PCell. A PSCell may be configuredwith PUCCH resources. In an example, when a SCG is configured, there maybe at least one SCG bearer or one split bearer. In an example, upondetection of a physical layer problem or a random access problem on aPSCell, or upon reaching a number of RLC retransmissions associated withthe SCG, or upon detection of an access problem on a PSCell during a SCGaddition or a SCG change: an RRC connection re-establishment proceduremay not be triggered, UL transmissions towards cells of an SCG may bestopped, a master base station may be informed by a UE of a SCG failuretype and DL data transfer over a master base station may be maintained.

In an example, a MAC sublayer may provide services such as data transferand radio resource allocation to upper layers (e.g. 1310 or 1320). A MACsublayer may comprise a plurality of MAC entities (e.g. 1350 and 1360).A MAC sublayer may provide data transfer services on logical channels.To accommodate different kinds of data transfer services, multiple typesof logical channels may be defined. A logical channel may supporttransfer of a particular type of information. A logical channel type maybe defined by what type of information (e.g., control or data) istransferred. For example, BCCH, PCCH, CCCH and DCCH may be controlchannels and DTCH may be a traffic channel. In an example, a first MACentity (e.g. 1310) may provide services on PCCH, BCCH, CCCH, DCCH, DTCHand MAC control elements. In an example, a second MAC entity (e.g. 1320)may provide services on BCCH, DCCH, DTCH and MAC control elements.

A MAC sublayer may expect from a physical layer (e.g. 1330 or 1340)services such as data transfer services, signaling of HARQ feedback,signaling of scheduling request or measurements (e.g. CQI). In anexample, in dual connectivity, two MAC entities may be configured for awireless device: one for MCG and one for SCG. A MAC entity of wirelessdevice may handle a plurality of transport channels. In an example, afirst MAC entity may handle first transport channels comprising a PCCHof MCG, a first BCH of MCG, one or more first DL-SCHs of MCG, one ormore first UL-SCHs of MCG and one or more first RACHs of MCG. In anexample, a second MAC entity may handle second transport channelscomprising a second BCH of SCG, one or more second DL-SCHs of SCG, oneor more second UL-SCHs of SCG and one or more second RACHs of SCG.

In an example, if a MAC entity is configured with one or more SCells,there may be multiple DL-SCHs and there may be multiple UL-SCHs as wellas multiple RACHs per MAC entity. In an example, there may be one DL-SCHand UL-SCH on a SpCell. In an example, there may be one DL-SCH, zero orone UL-SCH and zero or one RACH for an SCell. A DL-SCH may supportreceptions using different numerologies and/or TTI duration within a MACentity. A UL-SCH may also support transmissions using differentnumerologies and/or TTI duration within the MAC entity.

In an example, a MAC sublayer may support different functions and maycontrol these functions with a control (e.g. 1355 or 1365) element.Functions performed by a MAC entity may comprise mapping between logicalchannels and transport channels (e.g., in uplink or downlink),multiplexing (e.g. 1352 or 1362) of MAC SDUs from one or differentlogical channels onto transport blocks (TB) to be delivered to thephysical layer on transport channels (e.g., in uplink), demultiplexing(e.g. 1352 or 1362) of MAC SDUs to one or different logical channelsfrom transport blocks (TB) delivered from the physical layer ontransport channels (e.g., in downlink), scheduling information reporting(e.g., in uplink), error correction through HARQ in uplink or downlink(e.g. 1363), and logical channel prioritization in uplink (e.g. 1351 or1361). A MAC entity may handle a random access process (e.g. 1354 or1364).

FIG. 14 is an example diagram of a RAN architecture comprising one ormore base stations. In an example, a protocol stack (e.g. RRC, SDAP,PDCP, RLC, MAC, and PHY) may be supported at a node. A base station(e.g. gNB 120A or 120B) may comprise a base station central unit (CU)(e.g. gNB-CU 1420A or 1420B) and at least one base station distributedunit (DU) (e.g. gNB-DU 1430A, 1430B, 1430C, or 1430D) if a functionalsplit is configured. Upper protocol layers of a base station may belocated in a base station CU, and lower layers of the base station maybe located in the base station DUs. An F1 interface (e.g. CU-DUinterface) connecting a base station CU and base station DUs may be anideal or non-ideal backhaul. F1-C may provide a control plane connectionover an F1 interface, and F1-U may provide a user plane connection overthe F1 interface. In an example, an Xn interface may be configuredbetween base station CUs.

In an example, a base station CU may comprise an RRC function, an SDAPlayer, and a PDCP layer, and base station DUs may comprise an RLC layer,a MAC layer, and a PHY layer. In an example, various functional splitoptions between a base station CU and base station DUs may be possibleby locating different combinations of upper protocol layers (RANfunctions) in a base station CU and different combinations of lowerprotocol layers (RAN functions) in base station DUs. A functional splitmay support flexibility to move protocol layers between a base stationCU and base station DUs depending on service requirements and/or networkenvironments.

In an example, functional split options may be configured per basestation, per base station CU, per base station DU, per UE, per bearer,per slice, or with other granularities. In per base station CU split, abase station CU may have a fixed split option, and base station DUs maybe configured to match a split option of a base station CU. In per basestation DU split, a base station DU may be configured with a differentsplit option, and a base station CU may provide different split optionsfor different base station DUs. In per UE split, a base station (basestation CU and at least one base station DUs) may provide differentsplit options for different wireless devices. In per bearer split,different split options may be utilized for different bearers. In perslice splice, different split options may be applied for differentslices.

FIG. 15 is an example diagram showing RRC state transitions of awireless device. In an example, a wireless device may be in at least oneRRC state among an RRC connected state (e.g. RRC Connected 1530,RRC_Connected), an RRC idle state (e.g. RRC Idle 1510, RRC_Idle), and/oran RRC inactive state (e.g. RRC Inactive 1520, RRC_Inactive). In anexample, in an RRC connected state, a wireless device may have at leastone RRC connection with at least one base station (e.g. gNB and/or eNB),which may have a UE context of the wireless device. A UE context (e.g. awireless device context) may comprise at least one of an access stratumcontext, one or more radio link configuration parameters, bearer (e.g.data radio bearer (DRB), signaling radio bearer (SRB), logical channel,QoS flow, PDU session, and/or the like) configuration information,security information, PHY/MAC/RLC/PDCP/SDAP layer configurationinformation, and/or the like configuration information for a wirelessdevice. In an example, in an RRC idle state, a wireless device may nothave an RRC connection with a base station, and a UE context of awireless device may not be stored in a base station. In an example, inan RRC inactive state, a wireless device may not have an RRC connectionwith a base station. A UE context of a wireless device may be stored ina base station, which may be called as an anchor base station (e.g. lastserving base station).

In an example, a wireless device may transition a UE RRC state betweenan RRC idle state and an RRC connected state in both ways (e.g.connection release 1540 or connection establishment 1550; or connectionreestablishment) and/or between an RRC inactive state and an RRCconnected state in both ways (e.g. connection inactivation 1570 orconnection resume 1580). In an example, a wireless device may transitionits RRC state from an RRC inactive state to an RRC idle state (e.g.connection release 1560).

In an example, an anchor base station may be a base station that maykeep a UE context (a wireless device context) of a wireless device atleast during a time period that a wireless device stays in a RANnotification area (RNA) of an anchor base station, and/or that awireless device stays in an RRC inactive state. In an example, an anchorbase station may be a base station that a wireless device in an RRCinactive state was lastly connected to in a latest RRC connected stateor that a wireless device lastly performed an RNA update procedure in.In an example, an RNA may comprise one or more cells operated by one ormore base stations. In an example, a base station may belong to one ormore RNAs. In an example, a cell may belong to one or more RNAs.

In an example, a wireless device may transition a UE RRC state from anRRC connected state to an RRC inactive state in a base station. Awireless device may receive RNA information from the base station. RNAinformation may comprise at least one of an RNA identifier, one or morecell identifiers of one or more cells of an RNA, a base stationidentifier, an IP address of the base station, an AS context identifierof the wireless device, a resume identifier, and/or the like.

In an example, an anchor base station may broadcast a message (e.g. RANpaging message) to base stations of an RNA to reach to a wireless devicein an RRC inactive state, and/or the base stations receiving the messagefrom the anchor base station may broadcast and/or multicast anothermessage (e.g. paging message) to wireless devices in their coveragearea, cell coverage area, and/or beam coverage area associated with theRNA through an air interface.

In an example, when a wireless device in an RRC inactive state movesinto a new RNA, the wireless device may perform an RNA update (RNAU)procedure, which may comprise a random access procedure by the wirelessdevice and/or a UE context retrieve procedure. A UE context retrieve maycomprise: receiving, by a base station from a wireless device, a randomaccess preamble; and fetching, by a base station, a UE context of thewireless device from an old anchor base station. Fetching may comprise:sending a retrieve UE context request message comprising a resumeidentifier to the old anchor base station and receiving a retrieve UEcontext response message comprising the UE context of the wirelessdevice from the old anchor base station.

In an example embodiment, a wireless device in an RRC inactive state mayselect a cell to camp on based on at least a on measurement results forone or more cells, a cell where a wireless device may monitor an RNApaging message and/or a core network paging message from a base station.In an example, a wireless device in an RRC inactive state may select acell to perform a random access procedure to resume an RRC connectionand/or to transmit one or more packets to a base station (e.g. to anetwork). In an example, if a cell selected belongs to a different RNAfrom an RNA for a wireless device in an RRC inactive state, the wirelessdevice may initiate a random access procedure to perform an RNA updateprocedure. In an example, if a wireless device in an RRC inactive statehas one or more packets, in a buffer, to transmit to a network, thewireless device may initiate a random access procedure to transmit oneor more packets to a base station of a cell that the wireless deviceselects. A random access procedure may be performed with two messages(e.g. 2 stage random access) and/or four messages (e.g. 4 stage randomaccess) between the wireless device and the base station.

In an example embodiment, a base station receiving one or more uplinkpackets from a wireless device in an RRC inactive state may fetch a UEcontext of a wireless device by transmitting a retrieve UE contextrequest message for the wireless device to an anchor base station of thewireless device based on at least one of an AS context identifier, anRNA identifier, a base station identifier, a resume identifier, and/or acell identifier received from the wireless device. In response tofetching a UE context, a base station may transmit a path switch requestfor a wireless device to a core network entity (e.g. AMF, MME, and/orthe like). A core network entity may update a downlink tunnel endpointidentifier for one or more bearers established for the wireless devicebetween a user plane core network entity (e.g. UPF, S-GW, and/or thelike) and a RAN node (e.g. the base station), e.g. changing a downlinktunnel endpoint identifier from an address of the anchor base station toan address of the base station.

A gNB may communicate with a wireless device via a wireless networkemploying one or more new radio technologies. The one or more radiotechnologies may comprise at least one of: multiple technologies relatedto physical layer; multiple technologies related to medium accesscontrol layer; and/or multiple technologies related to radio resourcecontrol layer. Example embodiments of enhancing the one or more radiotechnologies may improve performance of a wireless network. Exampleembodiments may increase the system throughput, or data rate oftransmission. Example embodiments may reduce battery consumption of awireless device. Example embodiments may improve latency of datatransmission between a gNB and a wireless device. Example embodimentsmay improve network coverage of a wireless network. Example embodimentsmay improve transmission efficiency of a wireless network.

A gNB and/or a wireless device may have multiple antenna, to support atransmission with high data rate in a NR system. When configured withmultiple antennas, a wireless device may perform one or more beammanagement procedures, as shown in FIG. 9B.

A wireless device may perform a downlink beam management based on one ormore CSI-RSs, and/or one or more SSBs. In a beam management procedure, awireless device may measure a channel quality of a beam pair link. Thebeam pair link may comprise a transmitting beam from a gNB and areceiving beam at the wireless device. When configured with multiplebeams associated with multiple CSI-RSs or SSBs, a wireless device maymeasure the multiple beam pair links between the gNB and the wirelessdevice.

In an example, a wireless device may transmit one or more beammanagement reports to a gNB. In a beam management report, the wirelessdevice may indicate one or more beam pair quality parameters, comprisingat least, one or more beam identifications; RSRP; PMI/CQI/RI of at leasta subset of configured multiple beams.

In an example, a gNB and/or a wireless device may perform a downlinkbeam management procedure on one or multiple Transmission and ReceivingPoint (TRPs), as shown in FIG. 9B. Based on a wireless device's beammanagement report, a gNB may transmit to the wireless device a signalindicating that a new beam pair link is a serving beam. The gNB maytransmit PDCCH and PDSCH to the wireless device using the serving beam.

In an example, a wireless device or a gNB may trigger a beam failurerecovery mechanism. A wireless device may trigger a beam failurerecovery (BFR) procedure, e.g., when at least a beam failure occurs. Inan example, a beam failure may occur when quality of beam pair link(s)of at least one PDCCH falls below a threshold. The threshold may be aRSRP value (e.g., −140 dbm, −110 dbm) or a SINR value (e.g., −3 dB, −1dB), which may be configured in a RRC message.

FIG. 16A shows example of a first beam failure scenario. In the example,a gNB may transmit a PDCCH from a transmission (Tx) beam to a receiving(Rx) beam of a wireless device from a TRP. When the PDCCH on the beampair link (between the Tx beam of the gNB and the Rx beam of thewireless device) have a lower-than-threshold RSRP/SINR value due to thebeam pair link being blocked (e.g., by a moving car or a building), thegNB and the wireless device may start a beam failure recovery procedureon the TRP.

FIG. 16B shows example of a second beam failure scenario. In theexample, the gNB may transmit a PDCCH from a beam to a wireless devicefrom a first TRP. When the PDCCH on the beam is blocked, the gNB and thewireless device may start a beam failure recovery procedure on a newbeam on a second TRP.

In an example, a wireless device may measure quality of beam pair linkusing one or more RSs. The one or more RSs may be one or more SSBs, orone or more CSI-RS resources. A CSI-RS resource may be identified by aCSI-RS resource index (CRI). In an example, quality of beam pair linkmay be defined as a RSRP value, or a reference signal received quality(e.g. RSRQ) value, and/or a CSI (e.g., SINR) value measured on RSresources. In an example, a gNB may indicate whether an RS resource,used for measuring beam pair link quality, is QCLed (Quasi-Co-Located)with DM-RSs of a PDCCH. The RS resource and the DM-RSs of the PDCCH maybe called QCLed when the channel characteristics from a transmission onan RS to a wireless device, and that from a transmission on a PDCCH tothe wireless device, are similar or same under a configured criterion.In an example, The RS resource and the DM-RSs of the PDCCH may be calledQCLed when doppler shift and/or doppler shift of the channel from atransmission on an RS to a wireless device, and that from a transmissionon a PDCCH to the wireless device, are same.

In an example, a wireless device may monitor PDCCH on M beam (e.g. 2, 4,8) pair links simultaneously, where M≥1 and the value of M may depend atleast on capability of the wireless device. In an example, monitoring aPDCCH may comprise detecting a DCI via the PDCCH transmitted on commonsearch spaces and/or wireless device specific search spaces. In anexample, monitoring multiple beam pair links may increase robustnessagainst beam pair link blocking. In an example, a gNB may transmit oneor more messages comprising parameters indicating a wireless device tomonitor PDCCH on different beam pair link(s) in different OFDM symbols.

In an example, a gNB may transmit one or more RRC messages or MAC CEscomprising parameters indicating Rx beam setting of a wireless devicefor monitoring PDCCH on multiple beam pair links. A gNB may transmit anindication of spatial QCL between an DL RS antenna port(s) and DL RSantenna port(s) for demodulation of DL control channel. In an example,the indication may be a parameter in a MAC CE, or a RRC message, or aDCI, and/or combination of these signaling.

In an example, for reception of data packet on a PDSCH, a gNB mayindicate spatial QCL parameters between DL RS antenna port(s) and DM-RSantenna port(s) of DL data channel. A gNB may transmit DCI comprisingparameters indicating the RS antenna port(s) QCL-ed with DM-RS antennaport(s).

In an example, when a gNB transmits a signal indicating QCL parametersbetween CSI-RS and DM-RS for PDCCH, a wireless device may measure a beampair link quality based on CSI-RSs QCLed with DM-RS for PDCCH. In anexample, when multiple contiguous beam failures occur, the wirelessdevice may start a beam failure recovery (BFR) procedure.

In an example, a wireless device transmits a beam failure recoveryrequest (BFRQ) signal on an uplink physical channel to a gNB whenstarting a BFR procedure. The gNB may transmit a DCI via a PDCCH in acoreset in response to receiving the BFRQ signal on the uplink physicalchannel. The wireless may consider the BFR procedure successfullycompleted when receiving the DCI via the PDCCH in the coreset.

In an example, a gNB may transmit one or more messages comprisingconfiguration parameters of an uplink physical channel or signal fortransmitting a beam failure recovery request. The uplink physicalchannel or signal may be based on one of: a contention-free PRACH(BFR-PRACH), which may be a resource orthogonal to resources of otherPRACH transmissions; a PUCCH (BFR-PUCCH); and/or a contention-basedPRACH resource (CF-PRACH). Combinations of these candidatesignal/channels may be configured by the gNB. In an example, whenconfigured with multiple resources for a BFRQ signal, a wireless devicemay autonomously select a first resource for transmitting the BFRQsignal. In an example, when configured with a BFR-PRACH resource, aBFR-PUCCH resource, and a CF-PRACH resource, the wireless device mayselect the BFR-PRACH resource for transmitting the BFRQ signal. In anexample, when configured with a BFR-PRACH resource, a BFR-PUCCHresource, and a CF-PRACH resource, the gNB may transmit a message to thewireless device indicating a resource for transmitting the BFRQ signal.

In an example, a gNB may transmit a response to a wireless device afterreceiving one or more BFRQ signals. The response may comprise the CRIassociated with the candidate beam the wireless device indicates in theone or multiple BFRQ signals.

Example Downlink Control Information (DCI)

In an example, a gNB may transmit a DCI via a PDCCH for at least one of:scheduling assignment/grant; slot format notification; pre-emptionindication; and/or power-control commends. More specifically, the DCImay comprise at least one of: identifier of a DCI format; downlinkscheduling assignment(s); uplink scheduling grant(s); slot formatindicator; pre-emption indication; power-control for PUCCH/PUSCH; and/orpower-control for SRS.

In an example, a downlink scheduling assignment DCI may compriseparameters indicating at least one of: identifier of a DCI format; PDSCHresource indication; transport format; HARQ information; controlinformation related to multiple antenna schemes; and/or a command forpower control of the PUCCH.

In an example, an uplink scheduling grant DCI may comprise parametersindicating at least one of: identifier of a DCI format; PUSCH resourceindication; transport format; HARQ related information; and/or a powercontrol command of the PUSCH.

In an example, different types of control information may correspond todifferent DCI message sizes. For example, supporting multiple beamsand/or spatial multiplexing in the spatial domain and noncontiguousallocation of RBs in the frequency domain may require a largerscheduling message, in comparison with an uplink grant allowing forfrequency-contiguous allocation. DCI may be categorized into differentDCI formats, where a format corresponds to a certain message size and/orusage.

In an example, a wireless device may monitor one or more PDCCH fordetecting one or more DCI with one or more DCI format, in common searchspace or wireless device-specific search space. In an example, awireless device may monitor PDCCH with a limited set of DCI format, tosave power consumption. The more DCI format to be detected, the morepower be consumed at the wireless device.

In an example, the information in the DCI formats for downlinkscheduling may comprise at least one of: identifier of a DCI format;carrier indicator; RB allocation; time resource allocation; bandwidthpart indicator; HARQ process number; one or more MCS; one or more NDI;one or more RV; MIMO related information; Downlink assignment index(DAI); TPC for PUCCH; SRS request; and padding if necessary. In anexample, the MIMO related information may comprise at least one of: PMI;precoding information; transport block swap flag; power offset betweenPDSCH and reference signal; reference-signal scrambling sequence; numberof layers; and/or antenna ports for the transmission; and/orTransmission Configuration Indication (TCI).

In an example, the information in the DCI formats used for uplinkscheduling may comprise at least one of: an identifier of a DCI format;carrier indicator; bandwidth part indication; resource allocation type;RB allocation; time resource allocation; MCS; NDI; Phase rotation of theuplink DMRS; precoding information; CSI request; SRS request; Uplinkindex/DAI; TPC for PUSCH; and/or padding if necessary.

In an example, a gNB may perform CRC scrambling for a DCI, beforetransmitting the DCI via a PDCCH. The gNB may perform CRC scrambling bybinarily adding multiple bits of at least one wireless device identifier(e.g., C-RNTI, CS-RNTI, TPC-CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI, SPCSI C-RNTI, or TPC-SRS-RNTI) on the CRC bits of the DCI. The wirelessdevice may check the CRC bits of the DCI, when detecting the DCI. Thewireless device may receive the DCI when the CRC is scrambled by asequence of bits that is the same as the at least one wireless deviceidentifier.

In an example, in order to support wide bandwidth operation, a gNB maytransmit one or more PDCCH in different control resource sets(coresets). A gNB may transmit one or more RRC message comprisingconfiguration parameters of one or more coresets. A coreset may compriseat least one of: a first OFDM symbol; a number of consecutive OFDMsymbols; a set of resource blocks; a CCE-to-REG mapping. In an example,a gNB may transmit a PDCCH in a dedicated coreset for particularpurpose, for example, for beam failure recovery confirmation.

In an example, a wireless device may monitor PDCCH for detecting DCI inone or more configured coresets, to reduce the power consumption.

In an NR system, when configured with multiple beams, a gNB and/or awireless device may perform one or more beam management procedure. Forexample, the wireless device may perform a BFR procedure, if one or morebeam pair links between the gNB and the wireless device fail. Thewireless device may initiate a RA procedure for a BFR procedure for acell when a number of beam failure instances (e.g. contiguous) aredetected. The cell may be a PCell or a SCell. The cell may be a cellworking in licensed band or a cell working in unlicensed band. A beamfailure instance may occur when quality of a beam pair link is lowerthan a configured threshold. For example, a beam failure instance mayoccur when the RSRP value or SINR value of a beam pair link is lowerthan a first threshold, or the BLER (block error rate) of the beam pairlink is higher than a second threshold.

In existing BFR procedures, when a beam failure recovery timer (e.g.,beamFailureRecoveryTimer) is running, a wireless device may not selectand/or identify, from a plurality of reference signals, a referencesignal as a candidate beam which meets a selection criterion (e.g., RSRPvalue higher than a configured threshold). In existing BFR procedures,the wireless device may continue candidate beam selection, even when thebeamFailureRecoveryTimer expires. The wireless device, when employingexisting BFR procedures, may unnecessarily consumption power. Thewireless device, when employing existing BFR procedures, mayunnecessarily delay a beam failure recovery. In existing BFR procedures,the wireless device may not indicate to a base station that the wirelessdevice does not identify a candidate beam. A base station may not beaware of a situation in which a wireless device does not (or cannot)identify a candidate beam. In such case, existing BFR procedures mayresult in an inappropriate RRC (re-)configuration of candidate beams. Inexisting BFR procedures, after a wireless device declares (or indicates)a BFR procedure failure, a wireless device may: (1) keep monitoring aPDCCH in a first coreset, (2) miss PDCCH detection in a normal coreset,and/or (3) lose a connection with the base station. In existing BFRprocedures, the wireless device may unnecessarily initiate a randomaccess procedure when the wireless device indicates a radio link failurein response to a BFR procedure failure. Existing BFR procedures may beinefficient, take a long time, or increase battery power consumption.For example, the random access procedure may increase a duration of aBFR procedure and increase power consumption for the wireless device.Example embodiments provide processes for the wireless device and/or thebase station to enhance BFR procedures. Example embodiments may reduce aduration of a BFR procedure and may reduce battery power consumption.

FIG. 17 shows example of the BFR procedure. A wireless device mayreceive one or more RRC messages comprising BFR parameters 1701. The oneor more RRC messages may comprise one or more cell-specific orcell-common RRC messages (e.g., ServingCellConfig IE,ServingCellConfigCommon IE, or MAC-CellGroupConfig IE). The one or moreRRC messages may comprise: RRC connection reconfiguration message (e.g.,RRCReconfiguration); RRC connection reestablishment message (e.g.,RRCRestablishment); and/or RRC connection setup message (e.g.,RRCSetup).

In an example, the BFR parameters may comprise at least a firstthreshold for beam failure detection; at least a second threshold forselecting a beam(s); a first control resource set (e.g., coreset)associated with (or dedicated to) the BFR procedure. In an example, thefirst coreset may comprise multiple RBs in the frequency domain, atleast a symbol in the time domain. In an example, the first coreset maybe associated with the BFR procedure. The wireless device may monitor atleast a first PDCCH in the first coreset in response to transmitting aBFRQ signal indicating the beam failure. The wireless device may notmonitor the first PDCCH in the first coreset in response to nottransmitting the BFRQ signal. In an example, the gNB may not transmit aPDCCH in the first coreset if the gNB does not receive the BFRQ signalon an uplink resource. The gNB may transmit a PDCCH in a second coresetif the gNB does not receive the BFRQ signal. The second coreset, inwhich the wireless device may monitor a PDCCH before the BFR procedureis triggered, is different from the first coreset.

In an example, the BFR parameters may indicate a first set of RSs forbeam failure detection; and/or one or more PRACH resources associatedwith a second set of RSs (beams) for candidate beam selection. In anexample, the one or more PRACH resources may comprise at least one of:one or more preambles; and/or one or more time/frequency resources. Inan example, each RS of the second set of RSs may be associated with apreamble, a timer resource and/or a frequency resource of one of the oneor more PRACH resources.

In an example, the BFR parameters may indicate one or more PUCCH orscheduling request (SR) resources. In an example, the one or more PUCCHor SR resource may comprise at least one of: time allocation; frequencyallocation; cyclic shift; orthogonal cover code; and/or a spatialsetting. In an example, a BFRQ signal may be a PRACH preambletransmitted via a time/frequency resource of a PRACH resource. In anexample, a BFRQ signal may be a PUCCH/SR transmitted on a PUCCH/SRresource.

In an example, the first set of RSs may be one or more first CSI-RSs orone or more first SSBs. In an example, the second set of RSs may be oneor more second CSI-RSs or one or more second SSBs.

In an example, the BFR parameters may comprise at least one of: a firstnumber (e.g., beamFailureInstanceMaxCount) indicating a number of beamfailure instances which may trigger a RA procedure for the BFR; a firsttimer value of a beam failure detection timer (e.g.,beamFailureDetectionTimer), after an expiry of which, the wirelessdevice may reset a beam failure detection counter (e.g., BFI_COUNTER); asecond timer value of a beam failure recovery timer (e.g.,beamFailureRecoveryTimer) indicating a duration during which acontention-free RA for the BFR procedure may be performed; a secondnumber (e.g., preambleTransMax) indicating an allowed number of BFRQsignal transmissions; a third timer value of a response window (e.g.,ra-ResponseWindow) indicating a duration during which the wirelessdevice may receive a response from a gNB.

In an example, as shown in FIG. 17, the wireless device may perform beamfailure detections 1702, after receiving the one or more RRC messages.In an example, the physical layer of the wireless device may measure thefirst set of RSs. The physical layer may indicate one or more beamfailure instance or one or more beam non-failure instance periodicallyto the MAC entity of the wireless device, based on the at least firstthreshold. In an example, the physical layer may indicate a beam failureinstance when the measured quality (e.g., RSRP or SINR) of at least oneof the first set of RSs is lower than the at least first threshold. Inan example, the physical layer may indicate a beam non-failure instancewhen the measured quality (e.g., RSRP or SINR) of at least one of thefirst set of RSs is equal to or higher than the at least firstthreshold. In an example, the physical layer may skip indicating a beamnon-failure instance when the measured quality (e.g., RSRP or SINR) ofat least one of the first set of RSs is equal to or higher than the atleast first threshold. In an example, the periodicity of the indicationmay be a value configured by the gNB or be same as the periodicity oftransmission of the first set of RSs.

In an example, the MAC entity of the wireless device may set a beamfailure detection counter (e.g., BFICOUNTER) to a first value (e.g.,one) in response to receiving a first beam failure indication from thephysical layer. In an example, when receiving a contiguous second beamfailure indication, the MAC entity may increment the beam failuredetection counter (e.g., BFICOUNTER) (e.g., by one). In an example, whenreceiving a third beam non-failure indication, the MAC entity may resetthe beam failure detection counter (e.g., BFI_COUNTER) to a second value(e.g., zero).

In an example, when receiving a first beam failure indication from thephysical layer, the MAC entity may start the beam failure detectiontimer (e.g., beamFailureDetectionTimer) based on the first timer value.

In an example, a timer (e.g., beamFailureDetectionTimer,beamFailureRecoveryTimer, or ra-Response Window) may be running once itis started, until it is stopped or until it expires; otherwise the timermay not be running. A timer may be started if it is not running. A timermay be restarted if it is running. A timer may be started or restartedfrom its initial value. In an example, a timer may be implemented as acount-down timer from a first timer value down to a value (e.g., zero).In an example, the timer may be implemented as a count-up timer from avalue (e.g., zero) up to a first timer value. In an example, the timermay be implemented as a down-counter from a first counter value down toa value (e.g., zero). In an example, the timer may be implemented as acount-up counter from a value (e.g., zero) up to a first counter value.

When receiving a second beam failure indication from the physical layer,the MAC entity may increment the beam failure detection counter (e.g.,BFI_COUNTER) by a number (e.g., 1) and/or restart the beam failuredetection timer. When the beam failure detection timer expires, the MACentity may reset the beam failure detection counter (e.g., BFI_COUNTER)to an initial value.

In an example, when the beam failure detection counter indicates a valueequal to or greater than the first number (e.g.,beamFailureInstanceMaxCount), the MAC entity may initiate a RA (e.g.,contention-based or contention free) procedure for a BFR. In an example,when the beam failure detection counter indicates a value equal to orgreater than the first number (e.g., beamFailureInstanceMaxCount), theMAC entity may start the beam failure recovery timer (e.g.,beamFailureRecoveryTimer) based on the second timer value.

In an example, when initiating the RA procedure for the BFR, the MACentity may perform at least one of: resetting the beam failure detectioncounter to an initial value (e.g., zero); resetting the beam failuredetection timer; and/or indicating to the physical layer to stop beamfailure instance indication. In an example, the MAC entity may ignorethe beam failure instance indication, when triggering the RA procedurefor the BFR.

In an example, the MAC entity may request the physical layer to indicateat least a beam and/or the quality of the at least beam, in response tostarting the beam failure recovery timer or initiating the RA procedurefor the BFR. In an example, the physical layer of the wireless devicemay measure at least one of the second set of RSs. As shown in FIG. 17,the physical layer may select at least a beam 1703 based on the at leastsecond threshold. In an example, the at least beam may be identified bya CSI-RS resource index, or an SSB index. In an example, the physicallayer may select a beam when the measured quality (e.g., RSRP or SINR)of an RS associated the beam is greater than the at least secondthreshold.

In an example, as shown in FIG. 17, the MAC entity may select at least aBFRQ signal based on the at least beam and instruct the physical layerto transmit the at least BFRQ signal 1804 to a gNB, in response toreceiving the indication of the at least beam from the physical layer.In an example, the at least BFRQ signal may be a PRACH preambleassociated with the at least beam. In an example, the at least BFRQsignal may be a PUCCH/SR signal.

In an example, as shown in FIG. 17, the wireless device may startmonitoring a PDCCH 1705 for receiving a DCI as a response to thetransmitted BFRQ signal, at least in the first coreset, after a timeperiod since transmitting the at least BFRQ signal. The wireless devicemay start the response window (e.g., ra-Response Window orresponse-window) with a third timer value after the time period sincetransmitting the at least BFRQ signal. As shown in FIG. 17, The wirelessdevice may monitor the PDCCH for detecting a DCI 1706 in the firstcoreset during the response window.

In an example, as shown in FIG. 17, the wireless device may receive aDCI via the PDCCH at least in the first coreset in the response window.In 1707, the wireless device may consider the BFR procedure successfullycompleted in response to receiving the DCI via the PDCCH at least in thefirst coreset in the response window.

In an example, the wireless device may set a BFR transmission counter(e.g., PREAMBLE_TRANSMISSION_COUNTER) to a value (e.g., one) in responseto an expiry of the response window and not receiving the DCI. In anexample, in response to an expiry of the response window and notreceiving the DCI, the wireless device may perform one or more actionscomprising at least one of: transmitting at least a second BFRQ signal;starting the response window; and/or monitoring the PDCCH for a responseto the at least second BFRQ signal; incrementing the BFR transmissioncounter (e.g., PREAMBLE_TRANSMISSION_COUNTER) by a number (e.g., one) inresponse to an expiry of the response window and not receiving theresponse. The wireless device may repeat the one or more actions untilthe BFR procedure is successfully completed, or the beam failurerecovery timer expires. In an example, when the beam failure recoverytimer expires, and the wireless device does not receive the DCI, thewireless device may declare (or indicate) a BFR procedure failure 1708.In an example, when a number of transmissions of BFRQ signals is greaterthan a configured number, a wireless device may declare (or indicate) aBFR procedure failure.

FIG. 18 shows an example embodiment of a BFR. In an example, a basestation (e.g., gNB in FIG. 18) may transmit one or more RRC messages toa wireless device (e.g., UE in FIG. 18). The one or more RRC messagesmay be transmitted by implementing one or more of example embodiments asshown in FIG. 17 and above. In an example, the wireless device maydetect a number of beam failure instances (e.g., by implementing one ormore of example embodiments as shown in FIG. 17 and above). The wirelessdevice, in response to detecting the number of beam failure instances,may start a beam failure recovery timer (e.g., beamFailureRecoveryTimeras shown in FIG. 18) based on an initial timer value. The beam failurerecovery timer and the initial timer value may be configured in the oneor more RRC messages as described above and/or in FIG. 17. In anexample, when the beam failure recovery timer is running, the wirelessdevice may access radio link quality of reference signals foridentifying a reference signal as a candidate beam. In an example, aphysical layer of the wireless device may not identify from thereference signals, the reference signal which has higher channel quality(e.g., RSRP value) than a configured threshold. In an example, when thefailure recovery timer expires and the wireless device doesn't identifya candidate beam, the wireless device may complete the beam failurerecovery and/or report to higher layer (e.g., MAC or layer 3) of thewireless device information indicating that the beam failure recoveryfails due to no candidate beam being identified. According to an exampleembodiment, a wireless device may indicate to a base station (e.g., byan RRC reconnection message) that the wireless device does not identifya candidate beam. A base station, when receiving the RRC message, may beaware of the situation that the wireless device may not identify acandidate beam from a first plurality of reference signals. The basestation may reconfigure a second plurality of reference signals forcandidate beam selection in a future possible beam failure recovery forthe wireless device. The wireless device and/or the base station, byimplementing example embodiment(s), may: (1) reduce the delay of a beamfailure recovery, and/or (2) reduce the power consumption of thewireless device.

FIG. 19 shows an example embodiment of a BFR. In an example, a basestation (e.g., gNB in FIG. 19) may transmit one or more RRC messages toa wireless device (e.g., UE in FIG. 19). The one or more RRC messagesmay be transmitted by implementing one or more of example embodiments asshown in FIG. 17 and above. In an example, the wireless device maydetect a number of beam failure instances (e.g., by implementing one ormore of example embodiments as shown in FIG. 17 and above). The wirelessdevice, in response to detecting the number of beam failure instances,may start a beam failure recovery timer (e.g., beamFailureRecoveryTimer)based on an initial timer value. The beam failure recovery timer and theinitial timer value may be configured in the one or more RRC messages asdescribed above and/or in FIG. 17. In an example, when the beam failurerecovery timer is running, the wireless device may access radio linkquality of reference signals for identifying a reference signal as acandidate beam. In an example, a physical layer of the wireless devicemay not identify from the reference signals, the reference signal whichhas higher channel quality (e.g., RSRP value) than a configuredthreshold. In an example, when the wireless device doesn't identify acandidate beam, the wireless device may stop the beam failure recoverytimer. Stopping the beam failure recovery timer, in response to nocandidate beam being identified, may reduce a duration of a beam failurerecovery, or power consumption of the wireless device. In response tostopping the beam failure recovery timer, the wireless device maycomplete the beam failure recovery and/or report to higher layer (e.g.,MAC or layer 3) of the wireless device information indicating that thebeam failure recovery fails due to no candidate beam being identified.According to an example embodiment, a wireless device may indicate to abase station (e.g., by an RRC reconnection message) that the wirelessdevice does not identify a candidate beam. A base station, whenreceiving the RRC message, may be aware of the situation that thewireless device may not identify a candidate beam from a first pluralityof reference signals. The base station may reconfigure a secondplurality of reference signals for candidate beam selection in a futurepossible beam failure recovery for the wireless device. The wirelessdevice and/or the base station, by implementing the example embodiment,may: (1) reduce delay of a beam failure recovery, and/or (2) reduce thepower consumption of the wireless device.

FIG. 20 shows an example embodiment of a beam failure recovery. In anexample, a base station (e.g., gNB in FIG. 20) may transmit one or moreRRC messages to a wireless device (e.g., UE in FIG. 20). The one or moreRRC messages may be transmitted by implementing one or more of exampleembodiments as shown in FIG. 17 and above. In an example, the wirelessdevice may detect a number of beam failure instances (e.g., byimplementing one or more of example embodiments as shown in FIG. 17 andabove). The wireless device, in response to detecting the number of beamfailure instances, may start a beam failure recovery timer (e.g.,beamFailureRecoveryTimer) based on an initial timer value. The beamfailure recovery timer and the initial timer value may be configured inthe one or more RRC messages as described above and/or in FIG. 17.

In an example, as shown in FIG. 20, the wireless device may transmit afirst BFRQ signal at n₁ ^(th) slot, after selecting at least a beam. Thewireless device may start monitoring a first PDCCH in a first coreset at(n₁+k)^(th) slot. k may be a predefined value (e.g., four). The wirelessdevice may start a beam failure recovery response window (e.g.,ra-ResponseWindow, or bfr-response-window) at (n₁+k)^(th) slot inresponse to transmitting the first BFRQ signal. In an example, the beamfailure recovery response window may be a timer with a value configuredby the gNB. In an example, when the wireless device receives a DCI onthe first PDCCH at least in the first coreset before thebfr-response-window expires, the wireless device may consider the BFRprocedure successfully completed. The wireless device may stop thebeamFailureRecoveryTimer and/or stop the beam failure recovery responsewindow in response to the BFR procedure being successfully completed.

In an example, as shown in FIG. 20, when the beam failure recoveryresponse window expires at (n₁+k+1)^(th) slot and the wireless devicedoes not receive a DCI on the first PDCCH, the wireless device may starttransmitting a second BFRQ signal at n₂ ^(t) slot. In an example, 1 isthe length of the bfr-response-window, which may be configured in a RRCmessage or be a predefined value. In an example, when thebfr-response-window expires at (n₂+k+1)^(t) slot and the wireless devicemay not receive a DCI on the first PDCCH, the wireless device maytransmit multiple times of the BFRQ signal. In an example, the wirelessdevice may transmit the BFRQ signal at n_(m) ^(th) slot, and monitor thefirst PDCCH for detecting the DCI from (n_(m)+k)^(th) slot, untilreceiving the DCI before the (n_(m)+k+1)^(th) slot.

As shown in FIG. 20, the beam failure recovery response window may be inrunning when the beamFailureRecoveryTimer expires. The wireless devicemay be in monitoring the first PDCCH when the beamFailureRecoveryTimerexpires. The wireless device keeping monitoring the first PDCCH, whenthe beamFailureRecoveryTimer expires, may miss detecting a second PDCCHon a second control resource set. There is need to specify PDCCHmonitoring when the beamFailureRecoveryTimer expires. In an example, thewireless device may stop monitoring the first PDCCH in the first coresetin response to the beamFailureRecoveryTimer expiring. In an example, thewireless device may stop the beam failure recovery response window inresponse to the beamFailureRecoveryTimer expiring.

In an example, the wireless device may switch to monitor a second PDCCHin a second coreset in response to the beamFailureRecoveryTimerexpiring. The second coreset may be a coreset where the wireless devicemonitors a PDCCH before the BFR procedure is triggered.

In an example, when the beamFailureRecoveryTimer expires, the wirelessdevice may terminate the transmission of the at least BFRQ signal,and/or reset the BFRQ transmission counter (e.g., zero).

In an example, the MAC entity may indicate the physical layer to startbeam failure instance indication, in response to thebeamFailureRecoveryTimer expiring. In an example, the physical layer maymeasure the first set of RSs, and report beam failure or beamnon-failure instance periodically to the MAC entity. In the example, itmay avoid restarting BFR procedure if the wireless device detects a beamnon-failure instance.

In an example, the MAC entity may indicate the physical layer to reportat least a beam, in response to the beamFailureRecoveryTimer expiring.In the example, it may speed up beam failure recovery if the physicallayer starts reporting the at least beam, and skips beam failuredetection. The beam failure detection may take a long-time period.

In an example, a gNB may transmit one or more RRC messages comprising aback-off value. The MAC entity may indicate the physical layer to startbeam failure instance indication and/or new beam indication at aback-off time after the beamFailureRecoveryTimer expires. In an example,the back-off time may be selected (e.g., randomly) between zero and theback-off value.

In an example, the MAC entity may indicate the physical layer to sendbeam failure instance indication and/or new beam indication immediately,when the back-off value is set to zero.

In an example, the MAC entity may indicate the physical layer to stopbeam failure instance indication and/or new beam indication after thebeamFailureRecoveryTimer expires, when the back-off value is set to“infinity”.

In an example, the MAC entity may indicate to at least a higher layer(e.g., RRC) a first type of information, in response to thebeamFailureRecoveryTimer expiring. In an example, the first type ofinformation may be at least one of: random access problem; beam failurerecovery timer expiring; BFR procedure failure; out of synchronization.

In an example, the at least higher layer (e.g., RRC) may instruct lowerlayers (e.g., MAC or physical layer) to initiate a random access or acontention-based BFR procedure or a contention-free BFR procedure inresponse to receiving the first type of information. In an example, thecontention-free BFR procedure may be a PUCCH/SR/PRACH-based BFRprocedure, which may be same or different from the first BFR procedure.

In an example, the at least higher layer may not instruct the lowerlayers one or more actions, in response to receiving the first type ofinformation. In an example, the higher layers may ignore the first typeof information. In an example, the MAC entity may instruct the physicallayer to initiate a random access procedure or a contention-based BFRprocedure or a contention-free BFR procedure, in response to thebeamFailureRecoveryTimer expiring.

In an example, the gNB may set the beamFailureRecoveryTimer to“infinity”, in which case, the wireless device may repeat the BFRprocedure until successful receiving response from the gNB, or until theat least higher layer instruct lower layers to stop the BFR procedure.

By the embodiments, a wireless device may perform one or more actionswhen the beamFailureRecoveryTimer expires and the wireless device doesnot receive a response from a gNB. In an example, the one or moreactions may lead to reducing the power consumption of PDCCH monitoring,for example, by stopping monitoring the first coreset dedicated for theBFR procedure and/or switching to monitor a second coreset on which thewireless device monitors before the BFR procedure starts. In an example,the one or more actions may lead to reducing the power consumption oftransmitting the BFRQ signal, for example, by stopping transmitting theBFRQ signal. The one or more actions may lead to improve success rate ofthe BFR procedure, for example, by starting beam failure detectionand/or new beam selection.

In an example, the wireless device may start a beam failure recoverytimer (e.g., beamFailureRecoveryTimer) when detecting a number ofcontiguous beam failures. When the beamFailureRecoveryTimer is running,the wireless device may not select a candidate beam satisfying theselection requirement, for example, due to no RS from the second set ofRSs having a receiving quality (e.g., RSRP or SINR) than the at leastsecond threshold.

In an example, when no candidate beam indication received from thephysical layer during the beamFailureRecoveryTimer is running, the MACentity may indicate a second type of information to higher layers (e.g.,RRC) upon the beamFailureRecoveryTimer expiring. In an example, thesecond type of information may comprise at least one of: no beam beingselected; beam failure recovery procedure failure; and/or out ofsynchronization.

In an example, in response to an expiry of the beamFailureRecoveryTimerand no candidate beam indication received from the physical layer, thewireless device may perform at least one of: starting to detect one ormore beam failure instance; starting to select one or more new beam;initiating a random access procedure; indicating the second type ofinformation to higher layers.

In an example, a wireless device may start a beam failure recovery timer(e.g., beamFailureRecoveryTimer) when detecting a number of contiguousbeam failures. When the beamFailureRecoveryTimer is running, thewireless device may not select a new beam satisfying the selectionrequirement, for example, due to no RS from the second set of RSs havinga receiving quality (e.g., RSRP or SINR) than the at least secondthreshold. In an example, the physical layer of the wireless device mayindicate to the MAC entity of the wireless device that no new beam beselected. The MAC entity of the wireless device may stop thebeamFailureRecoveryTimer in response to receiving the indication. TheMAC entity of the wireless device may initiate a contention-based BFRprocedure, or a random access procedure. In an example, the MAC entitymay indicate a second type of information to higher layers (e.g., RRC)in response to receiving the indication from the physical layer. In anexample, the second type of information may comprise at least one of: nobeam being selected; beam failure recovery procedure failure; and/or outof synchronization.

In an example, a wireless device may receive from a base station one ormore messages comprising configuration parameters indicating: one ormore preambles; a first value of a response timer; a first coreset; asecond value of a BFR timer; and a second coreset. The wireless devicemay start the BFR timer in response to detecting at least one beamfailure. The wireless device may transmit, in a first slot, at least onepreamble of the one or more preambles. The wireless device may start theresponse timer after the first slot. The wireless device may monitor afirst PDCCH in the first coreset at least during a portion of a timeperiod when the response timer is running. In response to the BFR timerexpiring, when the response timer is running, the wireless device mayperform at least one of: stopping the monitoring the first PDCCH;stopping the response timer; and/or monitoring a second PDCCH in thesecond coreset.

In an example, the configuration parameters may comprise parameters of aBFR procedure.

In an example, the first coreset may comprise a first control resourceset comprising a first number of OFDM symbols and a first set ofresource blocks. In an example, the second coreset may comprise a secondnumber of OFDM symbols and a second set of resource blocks.

In an example, the at least one beam failure occurs when the quality ofthe beam is worse than a configured threshold.

In an example, the wireless device may consider the BFR proceduresuccessfully completed in response to receiving a DCI via the firstPDCCH in the first coreset, during the response timer is running. In anexample, the wireless device may stop the BFR timer and/or stop theresponse timer, in response to the BFR procedure successfully beingcompleted.

In an example, in response to the BFR timer expiring, the wirelessdevice may indicate to at least a higher layer (e.g., MAC or RRC layer)a first type of information comprising at least one of: the BFR timerexpiring; random access problem; no beam being selected; out ofsynchronization; the BFR procedure failure.

In an example, in response to the BFR timer expiring, the wirelessdevice may initiate at least one of: a random access procedure; startingto detect one or more beam failure instance; starting to select at leastone RS; and/or a BFR procedure.

Embodiments may be configured to operate as needed. The disclosedmechanism may be performed when certain criteria are met, for example,in a wireless device, a base station, a radio environment, a network, acombination of the above, and/or the like. Example criteria may bebased, at least in part, on for example, wireless device or network nodeconfigurations, traffic load, initial system set up, packet sizes,traffic characteristics, a combination of the above, and/or the like.When the one or more criteria are met, various example embodiments maybe applied. Therefore, it may be possible to implement exampleembodiments that selectively implement disclosed protocols.

A base station may communicate with a mix of wireless devices. Wirelessdevices and/or base stations may support multiple technologies, and/ormultiple releases of the same technology. Wireless devices may have somespecific capability(ies) depending on wireless device category and/orcapability(ies). A base station may comprise multiple sectors. When thisdisclosure refers to a base station communicating with a plurality ofwireless devices, this disclosure may refer to a subset of the totalwireless devices in a coverage area. This disclosure may refer to, forexample, a plurality of wireless devices of a given LTE or 5G releasewith a given capability and in a given sector of the base station. Theplurality of wireless devices in this disclosure may refer to a selectedplurality of wireless devices, and/or a subset of total wireless devicesin a coverage area which perform according to disclosed methods, and/orthe like. There may be a plurality of base stations or a plurality ofwireless devices in a coverage area that may not comply with thedisclosed methods, for example, because those wireless devices or basestations perform based on older releases of LTE or 5G technology.

According to various embodiments, a device such as, for example, awireless device, off-network wireless device, a base station, and/or thelike, may comprise one or more processors and memory. The memory maystore instructions that, when executed by the one or more processors,cause the device to perform a series of actions. Embodiments of exampleactions are illustrated in the accompanying figures and specification.Features from various embodiments may be combined to create yet furtherembodiments.

FIG. 21 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2120, a wireless device may initiate a beamfailure recovery procedure in response to detecting a number of beamfailure instances based on a first plurality of reference signals (at2110). At 2130, a beam failure recovery timer may be started with atimer value. The starting of the recovery timer may be in response tothe detecting. At 2140, a physical layer of the wireless device mayassess, during the beam failure recovery timer running, a first radiolink quality of a second plurality of reference signals against athreshold. At 2160, the beam failure recovery procedure may be completedin response to the beam failure recovery timer expiring and the firstradio link quality being below the threshold (at 2150). At 2170,information indicating that the beam failure recovery procedure faileddue to the first radio link quality being below the threshold may bereported to a radio resource control layer of the wireless device.

According to an example embodiment, the wireless device may receive froma base station, one or more radio resource control messages comprisingconfiguration parameters of the beam failure recovery procedure. Theconfiguration parameters may comprise the first plurality of referencesignals. The configuration parameters may comprise the second pluralityof reference signals. The configuration parameters may comprise thetimer value of the beam failure recovery timer. The configurationparameters may comprise the number of the beam failure instances.According to an example embodiment, the first plurality of referencesignals may comprise one or more CSI-RSs According to an exampleembodiment, the first plurality of reference signals may comprise one ormore synchronization signal blocks (SSBs). According to an exampleembodiment, the initiation of the beam failure recovery procedure maycomprise setting a preamble transmission counter to an initial value.According to an example embodiment, the first radio link quality maycomprise a value of reference signal received power (RSRP). According toan example embodiment, the threshold may be configured in a radioresource control message.

FIG. 22A is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. According to an example embodiment, at 2220, aMAC entity of the wireless device may ignore a beam failure instanceindication from a physical layer of the wireless device in response toinitiating the beam failure recovery procedure (at 2210). FIG. 22B is anexample flow diagram as per an aspect of an embodiment of the presentdisclosure. According to an example embodiment, at 2240, the beamfailure instance indication may be stopped by the physical layer of thewireless device in response to initiating the beam failure recoveryprocedure (at 2230).

According to an example embodiment, the first plurality of referencesignals may comprise one or more channel state information-referencesignals (CSI-RSs). According to an example embodiment, a beam failureinstance of the number of beam failure instances may occur when secondradio link quality measured based on the first plurality of referencesignals is worse than a first threshold. According to an exampleembodiment, the second radio link quality may comprise a value of blockerror rate (BLER).

According to an example embodiment, during the assessing, a referencesignal may be selected from the second plurality of reference signals inresponse to the first radio link quality of the reference signal beinggreater than the threshold. According to an example embodiment, apreamble associated with the reference signal may be transmitted.According to an example embodiment, the beam failure recovery timer maybe stopped in response to receiving a downlink control information for aresponse to the preamble. According to an example embodiment, the beamfailure recovery procedure may be completed in response to the downlinkcontrol information. FIG. 23A is an example flow diagram as per anaspect of an embodiment of the present disclosure. According to anexample embodiment, at 2320, the wireless device may select a secondreference signal at a back-off time after the beam failure recoverytimer expires in response to not receiving the downlink controlinformation (at 2310). According to an example embodiment, the back-offtime may be a value between zero and a configured back-off time value.FIG. 23B is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. According to an example embodiment, at 2340, thebeam failure recovery timer may be stopped in response to the firstradio link quality of one of the second plurality of reference signalsbeing below the threshold (at 2330). FIG. 24A is an example flow diagramas per an aspect of an embodiment of the present disclosure. Accordingto an example embodiment, at 2420, a preamble transmission counter maybe reset to an initial value in response to stopping the beam failurerecovery timer (at 2410). FIG. 24B is an example flow diagram as per anaspect of an embodiment of the present disclosure. According to anexample embodiment, at 2440, a contention-based random access procedurefor the beam failure recovery procedure may be initiated in response tostopping the beam failure recovery timer (at 2430). FIG. 25A is anexample flow diagram as per an aspect of an embodiment of the presentdisclosure. According to an example embodiment, at 2520, a MAC entity ofthe wireless device may ignore a beam failure instance indication from aphysical layer of the wireless device in response to initiating thecontention-based random access procedure for the beam failure recoveryprocedure (at 2510). FIG. 25B is an example flow diagram as per anaspect of an embodiment of the present disclosure. According to anexample embodiment, at 2540, a beam failure instance indication from aphysical layer of the wireless device may be stopped in response toinitiating the contention-based random access procedure for the beamfailure recovery procedure (at 2530). According to an exampleembodiment, the contention-based random access procedure may comprisetransmitting a preamble associated with a reference signal of aplurality of reference signals. According to an example embodiment, thecontention-based random access procedure may comprise monitoring adownlink control channel for a random access response. According to anexample embodiment, the contention-based random access procedure maycomprise receiving the random access response during the monitoring.

FIG. 26 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. According to an example embodiment, at 2610, awireless device may receive configuration parameters of a beam failurerecovery procedure. The configuration parameters may indicate a firstplurality of reference signals. The configuration parameters mayindicate a second plurality of reference signals. The configurationparameters may indicate a timer value of a beam failure recovery timer.At 2620, the wireless device may detect a number of beam failureinstances based on the first plurality of reference signals. At 2630,the beam failure recovery timer with the timer value may be started inresponse to the detecting (at 2620). At 2650, the wireless device mayaccess radio link quality of the second plurality of reference signalsagainst a threshold during a period when the beam failure recovery timeris running (2640). In response to the beam failure recovery timerexpiring at 2660, the beam failure recovery procedure may complete at2670. In response to the beam failure recovery timer expiring at 2660,one or more information may be reported to a higher layer of thewireless device at 2680. The one or more information may indicate theradio link quality is worse than the threshold.

FIG. 27 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. According to an example embodiment, at 2710, awireless device may receive configuration parameters of a beam failurerecovery procedure. The configuration parameters may indicate a firstcontrol resource set of a downlink control channel. The configurationparameters may indicate a timer value of a beam failure recovery timer.At 2730, the beam failure recovery timer may be started based on thetimer value in response to detecting a number of beam failure instances(2720). At 2740, a preamble may be transmitted for the beam failurerecovery procedure via a random access channel resource. At 2750, duringa response window, the wireless device may monitor a first downlinkcontrol channel in the first control resource set for a response to thepreamble. At 2770, monitoring the first downlink control channel may bestopped in response to an expiry of the beam failure recovery timer(2760). At 2780, a response timer associated with the response windowmay be stopped. At 2790, a second downlink control channel in a secondcontrol resource set may be monitored.

FIG. 28 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. According to an example embodiment, at 2810, awireless device may receive configuration parameters of a beam failurerecovery procedure. The configuration parameters may indicate a firstplurality of reference signals. The configuration parameters mayindicate a second plurality of reference signals. The configurationparameters may indicate a timer value of a beam failure recovery timer.At 2820, a number of beam failure instances based on the first pluralityof reference signals may be detected. At 2830, the beam failure recoverytimer may be started with the timer value in response to the detecting(2820). At 2840, radio link quality of the second plurality of referencesignals against a threshold during a period may be accessed when thebeam failure recovery timer is running. At 2860, the beam failurerecovery timer may be stopping in response to the radio link quality ofone of the second plurality of reference signals being greater than thethreshold (2850). At 2870, a preamble associated with the one of thesecond plurality of reference signals may be transmitted.

In this disclosure, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” Similarly, any termthat ends with the suffix “(s)” is to be interpreted as “at least one”and “one or more.” In this disclosure, the term “may” is to beinterpreted as “may, for example.” In other words, the term “may” isindicative that the phrase following the term “may” is an example of oneof a multitude of suitable possibilities that may, or may not, beemployed to one or more of the various embodiments.

If A and B are sets and every element of A is also an element of B, A iscalled a subset of B. In this specification, only non-empty sets andsubsets are considered. For example, possible subsets of B={cell1,cell2} are: {cell1}, {cell2}, and {cell1, cell2}. The phrase “based on”(or equally “based at least on”) is indicative that the phrase followingthe term “based on” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “in response to” (or equally “inresponse at least to”) is indicative that the phrase following thephrase “in response to” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “depending on” (or equally “depending atleast to”) is indicative that the phrase following the phrase “dependingon” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various embodiments.The phrase “employing/using” (or equally “employing/using at least”) isindicative that the phrase following the phrase “employing/using” is anexample of one of a multitude of suitable possibilities that may, or maynot, be employed to one or more of the various embodiments.

The term configured may relate to the capacity of a device whether thedevice is in an operational or non-operational state. Configured mayalso refer to specific settings in a device that effect the operationalcharacteristics of the device whether the device is in an operational ornon-operational state. In other words, the hardware, software, firmware,registers, memory values, and/or the like may be “configured” within adevice, whether the device is in an operational or nonoperational state,to provide the device with specific characteristics. Terms such as “acontrol message to cause in a device” may mean that a control messagehas parameters that may be used to configure specific characteristics ormay be used to implement certain actions in the device, whether thedevice is in an operational or non-operational state

In this disclosure, various embodiments are disclosed. Limitations,features, and/or elements from the disclosed example embodiments may becombined to create further embodiments within the scope of thedisclosure.

In this disclosure, parameters (or equally called, fields, orInformation elements: IEs) may comprise one or more information objects,and an information object may comprise one or more other objects. Forexample, if parameter (IE) N comprises parameter (IE) M, and parameter(IE) M comprises parameter (IE) K, and parameter (IE) K comprisesparameter (information element) J. Then, for example, N comprises K, andN comprises J. In an example embodiment, when one or more messagescomprise a plurality of parameters, it implies that a parameter in theplurality of parameters is in at least one of the one or more messages,but does not have to be in each of the one or more messages.

Furthermore, many features presented above are described as beingoptional through the use of “may” or the use of parentheses. For thesake of brevity and legibility, the present disclosure does notexplicitly recite each and every permutation that may be obtained bychoosing from the set of optional features. However, the presentdisclosure is to be interpreted as explicitly disclosing all suchpermutations. For example, a system described as having three optionalfeatures may be embodied in seven different ways, namely with just oneof the three possible features, with any two of the three possiblefeatures or with all three of the three possible features.

Many of the elements described in the disclosed embodiments may beimplemented as modules. A module is defined here as an element thatperforms a defined function and has a defined interface to otherelements. The modules described in this disclosure may be implemented inhardware, software in combination with hardware, firmware, wetware (i.e.hardware with a biological element) or a combination thereof, all ofwhich may be behaviorally equivalent. For example, modules may beimplemented as a software routine written in a computer languageconfigured to be executed by a hardware machine (such as C, C++,Fortran, Java, Basic, Matlab or the like) or a modeling/simulationprogram such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript.Additionally, it may be possible to implement modules using physicalhardware that incorporates discrete or programmable analog, digitaland/or quantum hardware. Examples of programmable hardware comprise:computers, microcontrollers, microprocessors, application-specificintegrated circuits (ASICs); field programmable gate arrays (FPGAs); andcomplex programmable logic devices (CPLDs). Computers, microcontrollersand microprocessors are programmed using languages such as assembly, C,C++ or the like. FPGAs, ASICs and CPLDs are often programmed usinghardware description languages (HDL) such as VHSIC hardware descriptionlanguage (VHDL) or Verilog that configure connections between internalhardware modules with lesser functionality on a programmable device. Theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the scope. In fact, after reading the abovedescription, it will be apparent to one skilled in the relevant art(s)how to implement alternative embodiments. Thus, the present embodimentsshould not be limited by any of the above described exemplaryembodiments.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposesonly. The disclosed architecture is sufficiently flexible andconfigurable, such that it may be utilized in ways other than thatshown. For example, the actions listed in any flowchart may bere-ordered or only optionally used in some embodiments.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112. Claims that do not expressly include the phrase “means for”or “step for” are not to be interpreted under 35 U.S.C. 112.

What is claimed is:
 1. A method comprising: initiating, by a wirelessdevice, a beam failure recovery procedure in response to detecting anumber of beam failure instances based on a first plurality of referencesignals; starting a beam failure recovery timer with a timer value inresponse to the detecting; assessing, by a physical layer of thewireless device and during the beam failure recovery timer beingrunning, first radio link quality of a second plurality of referencesignals against a threshold; completing the beam failure recoveryprocedure in response to the beam failure recovery timer expiring andthe first radio link quality being below the threshold; and reporting,to a radio resource control layer of the wireless device, informationindicating that the beam failure recovery procedure failed due to thefirst radio link quality being below the threshold.
 2. The method ofclaim 1, further comprising receiving, by the wireless device from abase station, one or more radio resource control messages comprisingconfiguration parameters of the beam failure recovery procedure, theconfiguration parameters comprising: the first plurality of referencesignals; the second plurality of reference signals; the timer value ofthe beam failure recovery timer; and the number of the beam failureinstances.
 3. The method of claim 1, wherein the first plurality ofreference signals comprise at least one of: one or more CSI-RSs; or oneor more synchronization signal blocks (SSBs).
 4. The method of claim 1,wherein initiating the beam failure recovery procedure comprises settinga preamble transmission counter to an initial value.
 5. The method ofclaim 1, wherein the first radio link quality is a value of referencesignal received power (RSRP).
 6. The method of claim 1, wherein thethreshold is configured in a radio resource control message.
 7. Themethod of claim 1, further comprising, in response to initiating thebeam failure recovery procedure, a MAC entity of the wireless deviceignoring a beam failure instance indication from a physical layer of thewireless device.
 8. The method of claim 1, further comprising, inresponse to initiating the beam failure recovery procedure, stopping abeam failure instance indication by the physical layer of the wirelessdevice.
 9. The method of claim 1, wherein the first plurality ofreference signals comprise one or more channel stateinformation-reference signals (CSI-RSs).
 10. The method of claim 1,wherein a beam failure instance of the number of beam failure instancesoccurs when second radio link quality measured based on the firstplurality of reference signals is worse than a first threshold.
 11. Themethod of claim 10, wherein the second radio link quality comprises avalue of block error rate (BLER).
 12. The method of claim 1, furthercomprising: selecting, during the assessing, a reference signal from thesecond plurality of reference signals in response to the first radiolink quality of the reference signal being greater than the threshold;transmitting a preamble associated with the reference signal; stoppingthe beam failure recovery timer in response to receiving a downlinkcontrol information for a response to the preamble; and completing thebeam failure recovery procedure in response to the downlink controlinformation.
 13. The method of claim 12, wherein the wireless deviceselects a second reference signal at a back-off time after the beamfailure recovery timer expires in response to not receiving the downlinkcontrol information.
 14. The method of claim 13, wherein the back-offtime is a value between zero and a configured back-off time value. 15.The method of claim 1, further comprising stopping the beam failurerecovery timer in response to the first radio link quality of one of thesecond plurality of reference signals being below the threshold.
 16. Themethod of claim 14, further comprising resetting a preamble transmissioncounter to an initial value in response to stopping the beam failurerecovery timer.
 17. The method of claim 14, further comprisinginitiating a contention-based random access procedure for the beamfailure recovery procedure in response to stopping the beam failurerecovery timer.
 18. The method of claim 17, further comprising ignoring,by a MAC entity of the wireless device, a beam failure instanceindication from a physical layer of the wireless device in response toinitiating the contention-based random access procedure for the beamfailure recovery procedure.
 19. The method of claim 17, furthercomprising stopping a beam failure instance indication from a physicallayer of the wireless device in response to initiating thecontention-based random access procedure for the beam failure recoveryprocedure.
 20. The method of claim 17, wherein the contention-basedrandom access procedure comprises: transmitting a preamble associatedwith a reference signal of a plurality of reference signals; monitoringa downlink control channel for a random access response; and receivingthe random access response during the monitoring.